diff --git a/Lib/pathlib/__init__.py b/Lib/pathlib/__init__.py
index cea1a9fe57eedf..9594c43b9bf4f7 100644
--- a/Lib/pathlib/__init__.py
+++ b/Lib/pathlib/__init__.py
@@ -209,7 +209,12 @@ def __hash__(self):
         try:
             return self._hash
         except AttributeError:
-            self._hash = hash(self._str_normcase)
+            if self.parser is posixpath:
+                self._hash = hash((self.root, tuple(self._tail)))
+            else:
+                self._hash = hash((self.drive.lower(),
+                                   self.root.lower(),
+                                   tuple([part.lower() for part in self._tail])))
             return self._hash
 
     def __eq__(self, other):
diff --git a/Misc/NEWS.d/next/Library/2025-09-08-19-04-23.gh-issue-138407.BqNAfi.rst b/Misc/NEWS.d/next/Library/2025-09-08-19-04-23.gh-issue-138407.BqNAfi.rst
new file mode 100644
index 00000000000000..c1606819675b69
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2025-09-08-19-04-23.gh-issue-138407.BqNAfi.rst
@@ -0,0 +1 @@
+Avoid useless join operation when calculate the hash vaule for pathlib.Path.