diff --git a/modules/openapi-generator/src/main/resources/typescript-angular/api.base.service.mustache b/modules/openapi-generator/src/main/resources/typescript-angular/api.base.service.mustache
index 87f4b24cce78..77c9e20e1f99 100644
--- a/modules/openapi-generator/src/main/resources/typescript-angular/api.base.service.mustache
+++ b/modules/openapi-generator/src/main/resources/typescript-angular/api.base.service.mustache
@@ -45,7 +45,7 @@ export class BaseService {
                 httpParams,
             );
         } else if (paramStyle === QueryParamStyle.Json) {
-            return httpParams.append(key, JSON.stringify(value));
+            return httpParams.append(key, JSON.stringify(value, (_, v) => v instanceof Set ? Array.from(v) : v));
         } else {
             // Form-style, SpaceDelimited or PipeDelimited
 
diff --git a/modules/openapi-generator/src/test/resources/3_0/query-param-json.yaml b/modules/openapi-generator/src/test/resources/3_0/query-param-json.yaml
index a943c346040e..e07c13b0cdff 100644
--- a/modules/openapi-generator/src/test/resources/3_0/query-param-json.yaml
+++ b/modules/openapi-generator/src/test/resources/3_0/query-param-json.yaml
@@ -15,6 +15,17 @@ paths:
             application/json:
               schema:
                 $ref: '#/components/schemas/Filter'
+        - in: query
+          name: tags
+          description: Tags
+          required: false
+          content:
+            application/json:
+              schema:
+                type: array
+                items:
+                  type: string
+                uniqueItems: true
 
       responses:
         '200':
diff --git a/samples/client/others/typescript-angular-v20/builds/query-param-deep-object/api.base.service.ts b/samples/client/others/typescript-angular-v20/builds/query-param-deep-object/api.base.service.ts
index 6999fb69b2e5..8ef269180c91 100644
--- a/samples/client/others/typescript-angular-v20/builds/query-param-deep-object/api.base.service.ts
+++ b/samples/client/others/typescript-angular-v20/builds/query-param-deep-object/api.base.service.ts
@@ -53,7 +53,7 @@ export class BaseService {
                 httpParams,
             );
         } else if (paramStyle === QueryParamStyle.Json) {
-            return httpParams.append(key, JSON.stringify(value));
+            return httpParams.append(key, JSON.stringify(value, (_, v) => v instanceof Set ? Array.from(v) : v));
         } else {
             // Form-style, SpaceDelimited or PipeDelimited
 
diff --git a/samples/client/others/typescript-angular-v20/builds/query-param-form-dot/api.base.service.ts b/samples/client/others/typescript-angular-v20/builds/query-param-form-dot/api.base.service.ts
index 497c080d6fd7..a5ce96389fe9 100644
--- a/samples/client/others/typescript-angular-v20/builds/query-param-form-dot/api.base.service.ts
+++ b/samples/client/others/typescript-angular-v20/builds/query-param-form-dot/api.base.service.ts
@@ -53,7 +53,7 @@ export class BaseService {
                 httpParams,
             );
         } else if (paramStyle === QueryParamStyle.Json) {
-            return httpParams.append(key, JSON.stringify(value));
+            return httpParams.append(key, JSON.stringify(value, (_, v) => v instanceof Set ? Array.from(v) : v));
         } else {
             // Form-style, SpaceDelimited or PipeDelimited
 
diff --git a/samples/client/others/typescript-angular-v20/builds/query-param-form/api.base.service.ts b/samples/client/others/typescript-angular-v20/builds/query-param-form/api.base.service.ts
index 312f99d4c190..3128dffcb8dc 100644
--- a/samples/client/others/typescript-angular-v20/builds/query-param-form/api.base.service.ts
+++ b/samples/client/others/typescript-angular-v20/builds/query-param-form/api.base.service.ts
@@ -53,7 +53,7 @@ export class BaseService {
                 httpParams,
             );
         } else if (paramStyle === QueryParamStyle.Json) {
-            return httpParams.append(key, JSON.stringify(value));
+            return httpParams.append(key, JSON.stringify(value, (_, v) => v instanceof Set ? Array.from(v) : v));
         } else {
             // Form-style, SpaceDelimited or PipeDelimited
 
diff --git a/samples/client/others/typescript-angular-v20/builds/query-param-json/api.base.service.ts b/samples/client/others/typescript-angular-v20/builds/query-param-json/api.base.service.ts
index 7fe22193a2c1..7343389e8ff7 100644
--- a/samples/client/others/typescript-angular-v20/builds/query-param-json/api.base.service.ts
+++ b/samples/client/others/typescript-angular-v20/builds/query-param-json/api.base.service.ts
@@ -53,7 +53,7 @@ export class BaseService {
                 httpParams,
             );
         } else if (paramStyle === QueryParamStyle.Json) {
-            return httpParams.append(key, JSON.stringify(value));
+            return httpParams.append(key, JSON.stringify(value, (_, v) => v instanceof Set ? Array.from(v) : v));
         } else {
             // Form-style, SpaceDelimited or PipeDelimited
 
diff --git a/samples/client/others/typescript-angular-v20/builds/query-param-json/api/default.service.ts b/samples/client/others/typescript-angular-v20/builds/query-param-json/api/default.service.ts
index d7733df8c4b2..e8d54af9174e 100644
--- a/samples/client/others/typescript-angular-v20/builds/query-param-json/api/default.service.ts
+++ b/samples/client/others/typescript-angular-v20/builds/query-param-json/api/default.service.ts
@@ -40,14 +40,15 @@ export class DefaultService extends BaseService {
     /**
      * @endpoint get /search
      * @param filter Filter
+     * @param tags Tags
      * @param observe set whether or not to return the data Observable as the body, response or events. defaults to returning the body.
      * @param reportProgress flag to report request and response progress.
      * @param options additional options
      */
-    public search(filter?: Filter, observe?: 'body', reportProgress?: boolean, options?: {httpHeaderAccept?: 'application/json', context?: HttpContext, transferCache?: boolean}): Observable<Response>;
-    public search(filter?: Filter, observe?: 'response', reportProgress?: boolean, options?: {httpHeaderAccept?: 'application/json', context?: HttpContext, transferCache?: boolean}): Observable<HttpResponse<Response>>;
-    public search(filter?: Filter, observe?: 'events', reportProgress?: boolean, options?: {httpHeaderAccept?: 'application/json', context?: HttpContext, transferCache?: boolean}): Observable<HttpEvent<Response>>;
-    public search(filter?: Filter, observe: any = 'body', reportProgress: boolean = false, options?: {httpHeaderAccept?: 'application/json', context?: HttpContext, transferCache?: boolean}): Observable<any> {
+    public search(filter?: Filter, tags?: Set<string>, observe?: 'body', reportProgress?: boolean, options?: {httpHeaderAccept?: 'application/json', context?: HttpContext, transferCache?: boolean}): Observable<Response>;
+    public search(filter?: Filter, tags?: Set<string>, observe?: 'response', reportProgress?: boolean, options?: {httpHeaderAccept?: 'application/json', context?: HttpContext, transferCache?: boolean}): Observable<HttpResponse<Response>>;
+    public search(filter?: Filter, tags?: Set<string>, observe?: 'events', reportProgress?: boolean, options?: {httpHeaderAccept?: 'application/json', context?: HttpContext, transferCache?: boolean}): Observable<HttpEvent<Response>>;
+    public search(filter?: Filter, tags?: Set<string>, observe: any = 'body', reportProgress: boolean = false, options?: {httpHeaderAccept?: 'application/json', context?: HttpContext, transferCache?: boolean}): Observable<any> {
 
         let localVarQueryParameters = new OpenApiHttpParams(this.encoder);
 
@@ -60,6 +61,15 @@ export class DefaultService extends BaseService {
         );
 
 
+        localVarQueryParameters = this.addToHttpParams(
+            localVarQueryParameters,
+            'tags',
+            <any>tags,
+            QueryParamStyle.Json,
+            false,
+        );
+
+
         let localVarHeaders = this.defaultHeaders;
 
         const localVarHttpHeaderAcceptSelected: string | undefined = options?.httpHeaderAccept ?? this.configuration.selectHeaderAccept([
diff --git a/samples/client/others/typescript-angular-v20/projects/app/src/api.query_param_json.spec.ts b/samples/client/others/typescript-angular-v20/projects/app/src/api.query_param_json.spec.ts
index 35960f072935..8833b3d55364 100644
--- a/samples/client/others/typescript-angular-v20/projects/app/src/api.query_param_json.spec.ts
+++ b/samples/client/others/typescript-angular-v20/projects/app/src/api.query_param_json.spec.ts
@@ -37,4 +37,13 @@ describe('JSON Query Param testing', () => {
     const req = httpTesting.expectOne(`http://localhost/search?filter=${filterJsonEncoded}`);
     expect(req.request.method).toEqual('GET');
   });
+
+  it('should serialize a Set query parameter as a JSON array', () => {
+    const tags = new Set(['a', 'b']);
+    const tagsJsonEncoded = encodeURIComponent('["a","b"]');
+
+    service.search(undefined, tags).subscribe();
+    const req = httpTesting.expectOne(`http://localhost/search?tags=${tagsJsonEncoded}`);
+    expect(req.request.method).toEqual('GET');
+  });
 });
diff --git a/samples/client/others/typescript-angular/builds/composed-schemas-tagged-unions/api.base.service.ts b/samples/client/others/typescript-angular/builds/composed-schemas-tagged-unions/api.base.service.ts
index a3f5732154dc..a82ce3db8a3a 100644
--- a/samples/client/others/typescript-angular/builds/composed-schemas-tagged-unions/api.base.service.ts
+++ b/samples/client/others/typescript-angular/builds/composed-schemas-tagged-unions/api.base.service.ts
@@ -53,7 +53,7 @@ export class BaseService {
                 httpParams,
             );
         } else if (paramStyle === QueryParamStyle.Json) {
-            return httpParams.append(key, JSON.stringify(value));
+            return httpParams.append(key, JSON.stringify(value, (_, v) => v instanceof Set ? Array.from(v) : v));
         } else {
             // Form-style, SpaceDelimited or PipeDelimited
 
diff --git a/samples/client/others/typescript-angular/builds/composed-schemas/api.base.service.ts b/samples/client/others/typescript-angular/builds/composed-schemas/api.base.service.ts
index a3f5732154dc..a82ce3db8a3a 100644
--- a/samples/client/others/typescript-angular/builds/composed-schemas/api.base.service.ts
+++ b/samples/client/others/typescript-angular/builds/composed-schemas/api.base.service.ts
@@ -53,7 +53,7 @@ export class BaseService {
                 httpParams,
             );
         } else if (paramStyle === QueryParamStyle.Json) {
-            return httpParams.append(key, JSON.stringify(value));
+            return httpParams.append(key, JSON.stringify(value, (_, v) => v instanceof Set ? Array.from(v) : v));
         } else {
             // Form-style, SpaceDelimited or PipeDelimited
 
diff --git a/samples/client/petstore/typescript-angular-v18-provided-in-root/builds/default/api.base.service.ts b/samples/client/petstore/typescript-angular-v18-provided-in-root/builds/default/api.base.service.ts
index be3fe1db2090..f3a7b34e9b49 100644
--- a/samples/client/petstore/typescript-angular-v18-provided-in-root/builds/default/api.base.service.ts
+++ b/samples/client/petstore/typescript-angular-v18-provided-in-root/builds/default/api.base.service.ts
@@ -53,7 +53,7 @@ export class BaseService {
                 httpParams,
             );
         } else if (paramStyle === QueryParamStyle.Json) {
-            return httpParams.append(key, JSON.stringify(value));
+            return httpParams.append(key, JSON.stringify(value, (_, v) => v instanceof Set ? Array.from(v) : v));
         } else {
             // Form-style, SpaceDelimited or PipeDelimited
 
diff --git a/samples/client/petstore/typescript-angular-v19-provided-in-root/builds/default/api.base.service.ts b/samples/client/petstore/typescript-angular-v19-provided-in-root/builds/default/api.base.service.ts
index be3fe1db2090..f3a7b34e9b49 100644
--- a/samples/client/petstore/typescript-angular-v19-provided-in-root/builds/default/api.base.service.ts
+++ b/samples/client/petstore/typescript-angular-v19-provided-in-root/builds/default/api.base.service.ts
@@ -53,7 +53,7 @@ export class BaseService {
                 httpParams,
             );
         } else if (paramStyle === QueryParamStyle.Json) {
-            return httpParams.append(key, JSON.stringify(value));
+            return httpParams.append(key, JSON.stringify(value, (_, v) => v instanceof Set ? Array.from(v) : v));
         } else {
             // Form-style, SpaceDelimited or PipeDelimited
 
diff --git a/samples/client/petstore/typescript-angular-v19-with-angular-dependency-params/builds/default/api.base.service.ts b/samples/client/petstore/typescript-angular-v19-with-angular-dependency-params/builds/default/api.base.service.ts
index be3fe1db2090..f3a7b34e9b49 100644
--- a/samples/client/petstore/typescript-angular-v19-with-angular-dependency-params/builds/default/api.base.service.ts
+++ b/samples/client/petstore/typescript-angular-v19-with-angular-dependency-params/builds/default/api.base.service.ts
@@ -53,7 +53,7 @@ export class BaseService {
                 httpParams,
             );
         } else if (paramStyle === QueryParamStyle.Json) {
-            return httpParams.append(key, JSON.stringify(value));
+            return httpParams.append(key, JSON.stringify(value, (_, v) => v instanceof Set ? Array.from(v) : v));
         } else {
             // Form-style, SpaceDelimited or PipeDelimited
 
diff --git a/samples/client/petstore/typescript-angular-v19/builds/default/api.base.service.ts b/samples/client/petstore/typescript-angular-v19/builds/default/api.base.service.ts
index be3fe1db2090..f3a7b34e9b49 100644
--- a/samples/client/petstore/typescript-angular-v19/builds/default/api.base.service.ts
+++ b/samples/client/petstore/typescript-angular-v19/builds/default/api.base.service.ts
@@ -53,7 +53,7 @@ export class BaseService {
                 httpParams,
             );
         } else if (paramStyle === QueryParamStyle.Json) {
-            return httpParams.append(key, JSON.stringify(value));
+            return httpParams.append(key, JSON.stringify(value, (_, v) => v instanceof Set ? Array.from(v) : v));
         } else {
             // Form-style, SpaceDelimited or PipeDelimited
 
diff --git a/samples/client/petstore/typescript-angular-v20-provided-in-root/builds/default/api.base.service.ts b/samples/client/petstore/typescript-angular-v20-provided-in-root/builds/default/api.base.service.ts
index be3fe1db2090..f3a7b34e9b49 100644
--- a/samples/client/petstore/typescript-angular-v20-provided-in-root/builds/default/api.base.service.ts
+++ b/samples/client/petstore/typescript-angular-v20-provided-in-root/builds/default/api.base.service.ts
@@ -53,7 +53,7 @@ export class BaseService {
                 httpParams,
             );
         } else if (paramStyle === QueryParamStyle.Json) {
-            return httpParams.append(key, JSON.stringify(value));
+            return httpParams.append(key, JSON.stringify(value, (_, v) => v instanceof Set ? Array.from(v) : v));
         } else {
             // Form-style, SpaceDelimited or PipeDelimited
 
diff --git a/samples/client/petstore/typescript-angular-v20/builds/default/api.base.service.ts b/samples/client/petstore/typescript-angular-v20/builds/default/api.base.service.ts
index be3fe1db2090..f3a7b34e9b49 100644
--- a/samples/client/petstore/typescript-angular-v20/builds/default/api.base.service.ts
+++ b/samples/client/petstore/typescript-angular-v20/builds/default/api.base.service.ts
@@ -53,7 +53,7 @@ export class BaseService {
                 httpParams,
             );
         } else if (paramStyle === QueryParamStyle.Json) {
-            return httpParams.append(key, JSON.stringify(value));
+            return httpParams.append(key, JSON.stringify(value, (_, v) => v instanceof Set ? Array.from(v) : v));
         } else {
             // Form-style, SpaceDelimited or PipeDelimited
 
diff --git a/samples/client/petstore/typescript-angular-v21-provided-in-root/builds/default/api.base.service.ts b/samples/client/petstore/typescript-angular-v21-provided-in-root/builds/default/api.base.service.ts
index be3fe1db2090..f3a7b34e9b49 100644
--- a/samples/client/petstore/typescript-angular-v21-provided-in-root/builds/default/api.base.service.ts
+++ b/samples/client/petstore/typescript-angular-v21-provided-in-root/builds/default/api.base.service.ts
@@ -53,7 +53,7 @@ export class BaseService {
                 httpParams,
             );
         } else if (paramStyle === QueryParamStyle.Json) {
-            return httpParams.append(key, JSON.stringify(value));
+            return httpParams.append(key, JSON.stringify(value, (_, v) => v instanceof Set ? Array.from(v) : v));
         } else {
             // Form-style, SpaceDelimited or PipeDelimited
 
diff --git a/samples/client/petstore/typescript-angular-v21/builds/default/api.base.service.ts b/samples/client/petstore/typescript-angular-v21/builds/default/api.base.service.ts
index be3fe1db2090..f3a7b34e9b49 100644
--- a/samples/client/petstore/typescript-angular-v21/builds/default/api.base.service.ts
+++ b/samples/client/petstore/typescript-angular-v21/builds/default/api.base.service.ts
@@ -53,7 +53,7 @@ export class BaseService {
                 httpParams,
             );
         } else if (paramStyle === QueryParamStyle.Json) {
-            return httpParams.append(key, JSON.stringify(value));
+            return httpParams.append(key, JSON.stringify(value, (_, v) => v instanceof Set ? Array.from(v) : v));
         } else {
             // Form-style, SpaceDelimited or PipeDelimited
 
diff --git a/samples/client/petstore/typescript-angular-v22-provided-in-root/builds/default/api.base.service.ts b/samples/client/petstore/typescript-angular-v22-provided-in-root/builds/default/api.base.service.ts
index be3fe1db2090..f3a7b34e9b49 100644
--- a/samples/client/petstore/typescript-angular-v22-provided-in-root/builds/default/api.base.service.ts
+++ b/samples/client/petstore/typescript-angular-v22-provided-in-root/builds/default/api.base.service.ts
@@ -53,7 +53,7 @@ export class BaseService {
                 httpParams,
             );
         } else if (paramStyle === QueryParamStyle.Json) {
-            return httpParams.append(key, JSON.stringify(value));
+            return httpParams.append(key, JSON.stringify(value, (_, v) => v instanceof Set ? Array.from(v) : v));
         } else {
             // Form-style, SpaceDelimited or PipeDelimited
 
diff --git a/samples/client/petstore/typescript-angular-v22-provided-in-root/builds/with-http-resource/api.base.service.ts b/samples/client/petstore/typescript-angular-v22-provided-in-root/builds/with-http-resource/api.base.service.ts
index f1be6d0471fa..19277d67f38e 100644
--- a/samples/client/petstore/typescript-angular-v22-provided-in-root/builds/with-http-resource/api.base.service.ts
+++ b/samples/client/petstore/typescript-angular-v22-provided-in-root/builds/with-http-resource/api.base.service.ts
@@ -53,7 +53,7 @@ export class BaseService {
                 httpParams,
             );
         } else if (paramStyle === QueryParamStyle.Json) {
-            return httpParams.append(key, JSON.stringify(value));
+            return httpParams.append(key, JSON.stringify(value, (_, v) => v instanceof Set ? Array.from(v) : v));
         } else {
             // Form-style, SpaceDelimited or PipeDelimited
 
diff --git a/samples/client/petstore/typescript-angular-v22/builds/default/api.base.service.ts b/samples/client/petstore/typescript-angular-v22/builds/default/api.base.service.ts
index be3fe1db2090..f3a7b34e9b49 100644
--- a/samples/client/petstore/typescript-angular-v22/builds/default/api.base.service.ts
+++ b/samples/client/petstore/typescript-angular-v22/builds/default/api.base.service.ts
@@ -53,7 +53,7 @@ export class BaseService {
                 httpParams,
             );
         } else if (paramStyle === QueryParamStyle.Json) {
-            return httpParams.append(key, JSON.stringify(value));
+            return httpParams.append(key, JSON.stringify(value, (_, v) => v instanceof Set ? Array.from(v) : v));
         } else {
             // Form-style, SpaceDelimited or PipeDelimited