diff --git a/pyarrow-stubs/__lib_pxi/io.pyi b/pyarrow-stubs/__lib_pxi/io.pyi
index f2d483a..488df00 100644
--- a/pyarrow-stubs/__lib_pxi/io.pyi
+++ b/pyarrow-stubs/__lib_pxi/io.pyi
@@ -117,6 +117,7 @@ class Buffer(_Weakrefable):
     def equals(self, other: Self) -> bool: ...
     def __reduce_ex__(self, protocol: SupportsIndex) -> str | tuple[Any, ...]: ...
     def to_pybytes(self) -> bytes: ...
+    def __buffer__(self, flags: int, /) -> memoryview: ...
 
 class ResizableBuffer(Buffer):
     def resize(self, new_size: int, shrink_to_fit: bool = False) -> None: ...
diff --git a/pyarrow-stubs/_stubs_typing.pyi b/pyarrow-stubs/_stubs_typing.pyi
index f2f28a7..29946e8 100644
--- a/pyarrow-stubs/_stubs_typing.pyi
+++ b/pyarrow-stubs/_stubs_typing.pyi
@@ -53,7 +53,8 @@ FilterTuple: TypeAlias = (
 class Buffer(Protocol):
     def __buffer__(self, flags: int, /) -> memoryview: ...
 
-SupportPyBuffer: TypeAlias = Any
+class SupportPyBuffer(Protocol):
+    def __buffer__(self, flags: int, /) -> memoryview: ...
 
 class SupportArrowStream(Protocol):
     def __arrow_c_stream__(self, requested_schema=None) -> Any: ...