diff --git a/stdlib/@tests/stubtest_allowlists/py314.txt b/stdlib/@tests/stubtest_allowlists/py314.txt
@@ -77,7 +77,6 @@ multiprocessing.forkserver.main
 multiprocessing.managers.BaseListProxy.clear
 multiprocessing.managers.BaseListProxy.copy
 multiprocessing.managers.DictProxy.__ior__
-multiprocessing.managers.SyncManager.set
 multiprocessing.managers._BaseDictProxy.__ior__
 multiprocessing.managers._BaseDictProxy.__or__
 multiprocessing.managers._BaseDictProxy.__reversed__
@@ -229,6 +228,12 @@ multiprocessing.managers._BaseDictProxy.keys
 multiprocessing.managers._BaseDictProxy.popitem
 multiprocessing.managers._BaseDictProxy.values
 
+multiprocessing.managers._BaseSetProxy.__iter__
+multiprocessing.managers._BaseSetProxy.__len__
+multiprocessing.managers._BaseSetProxy.clear
+multiprocessing.managers._BaseSetProxy.copy
+multiprocessing.managers._BaseSetProxy.pop
+
 # To match `dict`, we lie about the runtime, but use overloads to match the correct behavior
 types.MappingProxyType.get
 

diff --git a/stdlib/multiprocessing/managers.pyi b/stdlib/multiprocessing/managers.pyi
@@ -2,7 +2,17 @@ import queue
 import sys
 import threading
 from _typeshed import SupportsKeysAndGetItem, SupportsRichComparison, SupportsRichComparisonT
-from collections.abc import Callable, Iterable, Iterator, Mapping, MutableMapping, MutableSequence, Sequence
+from collections.abc import (
+    Callable,
+    Iterable,
+    Iterator,
+    Mapping,
+    MutableMapping,
+    MutableSequence,
+    MutableSet,
+    Sequence,
+    Set as AbstractSet,
+)
 from types import GenericAlias, TracebackType
 from typing import Any, AnyStr, ClassVar, Generic, SupportsIndex, TypeVar, overload
 from typing_extensions import Self, TypeAlias
@@ -18,6 +28,7 @@ __all__ = ["BaseManager", "SyncManager", "BaseProxy", "Token", "SharedMemoryMana
 _T = TypeVar("_T")
 _KT = TypeVar("_KT")
 _VT = TypeVar("_VT")
+_S = TypeVar("_S")
 
 class Namespace:
     def __init__(self, **kwds: Any) -> None: ...
@@ -111,6 +122,51 @@ else:
         def items(self) -> list[tuple[_KT, _VT]]: ...  # type: ignore[override]
         def values(self) -> list[_VT]: ...  # type: ignore[override]
 
+if sys.version_info >= (3, 14):
+    class _BaseSetProxy(BaseProxy, MutableSet[_T]):
+        __builtins__: ClassVar[dict[str, Any]]
+        # Copied from builtins.set
+        def add(self, element: _T, /) -> None: ...
+        def copy(self) -> set[_T]: ...
+        def clear(self) -> None: ...
+        def difference(self, *s: Iterable[Any]) -> set[_T]: ...
+        def difference_update(self, *s: Iterable[Any]) -> None: ...
+        def discard(self, element: _T, /) -> None: ...
+        def intersection(self, *s: Iterable[Any]) -> set[_T]: ...
+        def intersection_update(self, *s: Iterable[Any]) -> None: ...
+        def isdisjoint(self, s: Iterable[Any], /) -> bool: ...
+        def issubset(self, s: Iterable[Any], /) -> bool: ...
+        def issuperset(self, s: Iterable[Any], /) -> bool: ...
+        def pop(self) -> _T: ...
+        def remove(self, element: _T, /) -> None: ...
+        def symmetric_difference(self, s: Iterable[_T], /) -> set[_T]: ...
+        def symmetric_difference_update(self, s: Iterable[_T], /) -> None: ...
+        def union(self, *s: Iterable[_S]) -> set[_T | _S]: ...
+        def update(self, *s: Iterable[_T]) -> None: ...
+        def __len__(self) -> int: ...
+        def __contains__(self, o: object, /) -> bool: ...
+        def __iter__(self) -> Iterator[_T]: ...
+        def __and__(self, value: AbstractSet[object], /) -> set[_T]: ...
+        def __iand__(self, value: AbstractSet[object], /) -> Self: ...
+        def __or__(self, value: AbstractSet[_S], /) -> set[_T | _S]: ...
+        def __ior__(self, value: AbstractSet[_T], /) -> Self: ...  # type: ignore[override,misc]
+        def __sub__(self, value: AbstractSet[_T | None], /) -> set[_T]: ...
+        def __isub__(self, value: AbstractSet[object], /) -> Self: ...
+        def __xor__(self, value: AbstractSet[_S], /) -> set[_T | _S]: ...
+        def __ixor__(self, value: AbstractSet[_T], /) -> Self: ...  # type: ignore[override,misc]
+        def __le__(self, value: AbstractSet[object], /) -> bool: ...
+        def __lt__(self, value: AbstractSet[object], /) -> bool: ...
+        def __ge__(self, value: AbstractSet[object], /) -> bool: ...
+        def __gt__(self, value: AbstractSet[object], /) -> bool: ...
+        def __eq__(self, value: object, /) -> bool: ...
+        def __rand__(self, value: AbstractSet[object], /) -> set[_T]: ...
+        def __ror__(self, value: AbstractSet[_S], /) -> set[_T | _S]: ...  # type: ignore[misc]
+        def __rsub__(self, value: AbstractSet[_T], /) -> set[_T]: ...
+        def __rxor__(self, value: AbstractSet[_S], /) -> set[_T | _S]: ...  # type: ignore[misc]
+        def __class_getitem__(cls, item: Any, /) -> GenericAlias: ...
+
+    class SetProxy(_BaseSetProxy[_T]): ...
+
 class BaseListProxy(BaseProxy, MutableSequence[_T]):
     __builtins__: ClassVar[dict[str, Any]]
     def __len__(self) -> int: ...
@@ -273,6 +329,11 @@ class SyncManager(BaseManager):
     def list(self, sequence: Sequence[_T], /) -> ListProxy[_T]: ...
     @overload
     def list(self) -> ListProxy[Any]: ...
+    if sys.version_info >= (3, 14):
+        @overload
+        def set(self, iterable: Iterable[_T], /) -> SetProxy[_T]: ...
+        @overload
+        def set(self) -> SetProxy[Any]: ...
 
 class RemoteError(Exception): ...