diff -r 95d1adf144ee Doc/library/shutil.rst
--- a/Doc/library/shutil.rst	Sat Nov 03 14:37:37 2012 +0200
+++ b/Doc/library/shutil.rst	Sat Nov 03 16:02:00 2012 +0200
@@ -353,6 +353,14 @@
    .. versionadded:: 3.3
 
 
+.. function :: get_default_shell_path()
+
+  Return the path to default shell.
+
+  For unix system returns path to `sh`, for windows returns path to `cmd.exe`.
+
+  .. versionadded:: 3.4
+
 .. exception:: Error
 
    This exception collects exceptions that are raised during a multi-file
diff -r 95d1adf144ee Lib/shutil.py
--- a/Lib/shutil.py	Sat Nov 03 14:37:37 2012 +0200
+++ b/Lib/shutil.py	Sat Nov 03 16:02:00 2012 +0200
@@ -1106,3 +1106,11 @@
                 if _access_check(name, mode):
                     return name
     return None
+
+
+def get_default_shell_path():
+    """Return the path to default shell."""
+    if sys.platform == "win32":
+        return which('cmd.exe')
+    else:
+        return which('sh')
diff -r 95d1adf144ee Lib/test/test_shutil.py
--- a/Lib/test/test_shutil.py	Sat Nov 03 14:37:37 2012 +0200
+++ b/Lib/test/test_shutil.py	Sat Nov 03 16:02:00 2012 +0200
@@ -1622,9 +1622,27 @@
         self.assertEqual(expected, actual)
 
 
+class TestGetDefaultShellPath(unittest.TestCase):
+    def test_get_default_shell_path(self):
+        shell = shutil.get_default_shell_path()
+        param = "/c" if sys.platform == 'win32' else "-c"
+        s = subprocess.Popen([shell, param, "echo test"],
+                                stdout=subprocess.PIPE)
+        stdout, stderr = s.communicate()
+        self.assertIn(b"test", stdout)
+        self.assertIsNone(stderr)
+        self.assertEqual(0, s.returncode)
+
+
 def test_main():
-    support.run_unittest(TestShutil, TestMove, TestCopyFile,
-                         TermsizeTests, TestWhich)
+    support.run_unittest(
+        TestShutil,
+        TestMove,
+        TestCopyFile,
+        TermsizeTests,
+        TestWhich,
+        TestGetDefaultShellPath,
+    )
 
 if __name__ == '__main__':
     test_main()