diff --git a/.github/workflows/import.yml b/.github/workflows/import.yml
index 8a110616b..89cb1a6f5 100644
--- a/.github/workflows/import.yml
+++ b/.github/workflows/import.yml
@@ -13,7 +13,7 @@ jobs:
 
     strategy:
       matrix:
-        python-version: ['3.10', '3.11', '3.12', '3.13', '3.14']
+        python-version: ['3.11', '3.12', '3.13', '3.14', '3.15']
 
     steps:
       - name: Checkout repository
diff --git a/.github/workflows/mypy.yml b/.github/workflows/mypy.yml
index 40a19eb98..c096bc4fe 100644
--- a/.github/workflows/mypy.yml
+++ b/.github/workflows/mypy.yml
@@ -17,7 +17,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: ['3.10', '3.11', '3.12', '3.13', '3.14']
+        python-version: ['3.11', '3.12', '3.13', '3.14', '3.15']
 
     steps:
       - name: Checkout code
diff --git a/google/genai/types.py b/google/genai/types.py
index 70fdf9227..7a18e2a6d 100644
--- a/google/genai/types.py
+++ b/google/genai/types.py
@@ -25,7 +25,7 @@
 import sys
 import types as builtin_types
 import typing
-from typing import Annotated, Any, Callable, Dict, List, Literal, Optional, Sequence, Union, _UnionGenericAlias  # type: ignore
+from typing import Annotated, Any, Callable, Dict, List, Literal, Optional, Sequence, Union
 import pydantic
 from pydantic import ConfigDict, Field, PrivateAttr, WrapValidator, model_validator
 from typing_extensions import Self, TypedDict
@@ -37,14 +37,20 @@
     _UploadToFileSearchStoreOperation_from_mldev,
 )
 
-if sys.version_info >= (3, 10):
-  # Supports both Union[t1, t2] and t1 | t2
-  VersionedUnionType = Union[builtin_types.UnionType, _UnionGenericAlias]
+if typing.TYPE_CHECKING:
+  # Type checkers have always seen this as Any, which lets SchemaUnion accept
+  # any schema (e.g. Optional[X]). Keep it that way.
+  VersionedUnionType = Any
+  _UNION_TYPES = (typing.Union, builtin_types.UnionType)
+elif sys.version_info >= (3, 14):
+  # Union[t1, t2] and t1 | t2 both create builtin_types.UnionType, and
+  # typing._UnionGenericAlias is deprecated.
+  VersionedUnionType = builtin_types.UnionType
   _UNION_TYPES = (typing.Union, builtin_types.UnionType)
 else:
-  # Supports only Union[t1, t2]
-  VersionedUnionType = _UnionGenericAlias
-  _UNION_TYPES = (typing.Union,)
+  # Supports both Union[t1, t2] and t1 | t2
+  VersionedUnionType = Union[builtin_types.UnionType, typing._UnionGenericAlias]  # type: ignore
+  _UNION_TYPES = (typing.Union, builtin_types.UnionType)
 
 _is_pillow_image_imported = False
 if typing.TYPE_CHECKING:
diff --git a/pyproject.toml b/pyproject.toml
index 0ca787c15..21c03645a 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -7,7 +7,7 @@ version = "2.33.0"
 description = "GenAI Python SDK"
 readme = "README.md"
 license = "Apache-2.0"
-requires-python = ">=3.10"
+requires-python = ">=3.11"
 authors = [
     { name = "Google LLC", email = "googleapis-packages@google.com" },
 ]
@@ -16,11 +16,11 @@ classifiers = [
     "Operating System :: OS Independent",
     "Programming Language :: Python",
     "Programming Language :: Python :: 3",
-    "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
     "Programming Language :: Python :: 3.12",
     "Programming Language :: Python :: 3.13",
     "Programming Language :: Python :: 3.14",
+    "Programming Language :: Python :: 3.15",
     "Topic :: Internet",
     "Topic :: Software Development :: Libraries :: Python Modules",
 ]
diff --git a/requirements.txt b/requirements.txt
index 4583be06a..c8f6e0aa4 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -12,13 +12,16 @@ google-auth==2.56.0
 idna==3.18
 iniconfig==2.0.0
 packaging==24.2
-pillow==11.0.0
+pillow==11.0.0; python_version < '3.15'
+pillow==12.3.0; python_version >= '3.15'
 pluggy==1.5.0
 py==1.11.0
 pyasn1==0.6.1
 pyasn1_modules==0.4.1
-pydantic==2.12.0
-pydantic_core==2.41.1
+pydantic==2.12.0; python_version < '3.15'
+pydantic==2.14.1; python_version >= '3.15'
+pydantic_core==2.41.1; python_version < '3.15'
+pydantic_core==2.50.1; python_version >= '3.15'
 pyopenssl==24.2.1
 pytest==8.3.4
 pytest-asyncio==0.25.0