diff --git a/Tests/test_imagetk.py b/Tests/test_imagetk.py
index 4484dca1064..85ad116510b 100644
--- a/Tests/test_imagetk.py
+++ b/Tests/test_imagetk.py
@@ -112,3 +112,13 @@ def test_bitmapimage() -> None:
 
     with pytest.raises(ValueError):
         ImageTk.BitmapImage()
+
+
+def test_show_deprecated() -> None:
+    im = hopper()
+
+    with pytest.warns(DeprecationWarning):
+        try:
+            ImageTk._show(im, "test")
+        except tk.TclError:
+            pass
diff --git a/docs/deprecations.rst b/docs/deprecations.rst
index 634cee6894c..6e7a0bf0302 100644
--- a/docs/deprecations.rst
+++ b/docs/deprecations.rst
@@ -193,6 +193,14 @@ Image.Image.get_child_images()
 method uses an image's file pointer, and so child images could only be retrieved from
 an :py:class:`PIL.ImageFile.ImageFile` instance.
 
+ImageTk._show()
+^^^^^^^^^^^^^^^
+
+.. deprecated:: 11.2.0
+
+``ImageTk._show()`` has been deprecated, as it was an unused helper for
+:py:meth:`.Image.Image.show`.
+
 Removed features
 ----------------
 
diff --git a/docs/releasenotes/11.2.0.rst b/docs/releasenotes/11.2.0.rst
index f7e644cf32d..7e6a7a534a4 100644
--- a/docs/releasenotes/11.2.0.rst
+++ b/docs/releasenotes/11.2.0.rst
@@ -33,6 +33,14 @@ Image.Image.get_child_images()
 method uses an image's file pointer, and so child images could only be retrieved from
 an :py:class:`PIL.ImageFile.ImageFile` instance.
 
+ImageTk._show()
+^^^^^^^^^^^^^^^
+
+.. deprecated:: 11.2.0
+
+``ImageTk._show()`` has been deprecated, as it was an unused helper for
+:py:meth:`.Image.Image.show`.
+
 API Changes
 ===========
 
diff --git a/src/PIL/ImageTk.py b/src/PIL/ImageTk.py
index bf29fdba54c..c0f62cb14e4 100644
--- a/src/PIL/ImageTk.py
+++ b/src/PIL/ImageTk.py
@@ -31,6 +31,7 @@
 from typing import TYPE_CHECKING, Any, cast
 
 from . import Image, ImageFile
+from ._deprecate import deprecate
 
 if TYPE_CHECKING:
     from ._typing import CapsuleType
@@ -266,8 +267,6 @@ def getimage(photo: PhotoImage) -> Image.Image:
 
 
 def _show(image: Image.Image, title: str | None) -> None:
-    """Helper for the Image.show method."""
-
     class UI(tkinter.Label):
         def __init__(self, master: tkinter.Toplevel, im: Image.Image) -> None:
             self.image: BitmapImage | PhotoImage
@@ -281,6 +280,7 @@ def __init__(self, master: tkinter.Toplevel, im: Image.Image) -> None:
                 image = self.image
             super().__init__(master, image=image, bg="black", bd=0)
 
+    deprecate("ImageTk._show", 13)
     if not getattr(tkinter, "_default_root"):
         msg = "tkinter not initialized"
         raise OSError(msg)