diff --git a/django/middleware/common.py b/django/middleware/common.py
index 12d006127b..9f71b9d278 100644
--- a/django/middleware/common.py
+++ b/django/middleware/common.py
@@ -78,12 +78,12 @@ class CommonMiddleware(MiddlewareMixin):
         Return the full path of the request with a trailing slash appended.
 
         Raise a RuntimeError if settings.DEBUG is True and request.method is
-        POST, PUT, or PATCH.
+        DELETE, POST, PUT, or PATCH.
         """
         new_path = request.get_full_path(force_append_slash=True)
         # Prevent construction of scheme relative urls.
         new_path = escape_leading_slashes(new_path)
-        if settings.DEBUG and request.method in ("POST", "PUT", "PATCH"):
+        if settings.DEBUG and request.method in ("DELETE", "POST", "PUT", "PATCH"):
             raise RuntimeError(
                 "You called this URL via %(method)s, but the URL doesn't end "
                 "in a slash and you have APPEND_SLASH set. Django can't "
diff --git a/tests/middleware/tests.py b/tests/middleware/tests.py
index 2153a0bb5a..4dc1c83c42 100644
--- a/tests/middleware/tests.py
+++ b/tests/middleware/tests.py
@@ -107,11 +107,11 @@ class CommonMiddlewareTest(SimpleTestCase):
         self.assertEqual(resp.url, "/slash/?test=slash/")
 
     @override_settings(APPEND_SLASH=True, DEBUG=True)
-    def test_append_slash_no_redirect_on_POST_in_DEBUG(self):
+    def test_append_slash_no_redirect_in_DEBUG(self):
         """
         While in debug mode, an exception is raised with a warning
-        when a failed attempt is made to POST, PUT, or PATCH to an URL which
-        would normally be redirected to a slashed version.
+        when a failed attempt is made to DELETE, POST, PUT, or PATCH to an URL
+        which would normally be redirected to a slashed version.
         """
         msg = "maintaining %s data. Change your form to point to testserver/slash/"
         request = self.rf.get("/slash")
@@ -126,6 +126,9 @@ class CommonMiddlewareTest(SimpleTestCase):
         request.method = "PATCH"
         with self.assertRaisesMessage(RuntimeError, msg % request.method):
             CommonMiddleware(get_response_404)(request)
+        request = self.rf.delete("/slash")
+        with self.assertRaisesMessage(RuntimeError, msg % request.method):
+            CommonMiddleware(get_response_404)(request)
 
     @override_settings(APPEND_SLASH=False)
     def test_append_slash_disabled(self):