diff --git a/keystone/identity/backends/ldap/common.py b/keystone/identity/backends/ldap/common.py
index f8785e9c14..23d426c725 100644
--- a/keystone/identity/backends/ldap/common.py
+++ b/keystone/identity/backends/ldap/common.py
@@ -1402,20 +1402,31 @@ class BaseLdap(object):
             raise ValueError('"%(attr)s" is not a valid value for'
                              ' "%(attr_name)s"' % {'attr': attr,
                                                    'attr_name': attr_name})
+
+        # consider attr = "cn" and
+        # ldap_result = [{'uid': ['fake_id1']}, , 'cN': ["name"]}]
+        # doing lower case on both user_name_attribute and ldap users
+        # attribute
         result = []
         # consider attr = "cn" and
-        # ldap_result = [{'uid': ['fake_id1']},
-        #                {'uid': ['fake_id2'], 'cn': ['     ']},
-        #                {'uid': ['fake_id3'], 'cn': ['']},
-        #                {'uid': ['fake_id4'], 'cn': []},
-        #                {'uid': ['fake_id5'], 'cn': ["name"]}]
+        # ldap_result = [(u'cn=fake1,o=ex_domain', {'uid': ['fake_id1']}),
+        #                (u'cn=fake2,o=ex_domain', {'uid': ['fake_id2'],
+        #                'cn': ['     ']}),
+        #                (u'cn=fake3,o=ex_domain', {'uid': ['fake_id3'],
+        #                'cn': ['']}),
+        #                (u'cn=fake4,o=ex_domain', {'uid': ['fake_id4'],
+        #                'cn': []}),
+        #                (u'cn=fake5,o=ex_domain', {'uid': ['fake_id5'],
+        #                'cn': ["name"]})]
         for obj in ldap_result:
             # ignore ldap object(user/group entry) which has no attr set
             # in it or whose value is empty list.
-            if obj[1].get(attr):
-                # ignore ldap object whose attr value has empty strings or
-                # contains only whitespaces.
-                if obj[1].get(attr)[0] and obj[1].get(attr)[0].strip():
+            ldap_res_low_keys_dict = {k.lower(): v for k, v in obj[1].items()}
+            result_attr_vals = ldap_res_low_keys_dict.get(attr.lower())
+            # ignore ldap object whose attr value has empty strings or
+            # contains only whitespaces.
+            if result_attr_vals:
+                if result_attr_vals[0] and result_attr_vals[0].strip():
                     result.append(obj)
         # except {'uid': ['fake_id5'], 'cn': ["name"]}, all entries
         # will be ignored in ldap_result
diff --git a/keystone/tests/unit/test_backend_ldap.py b/keystone/tests/unit/test_backend_ldap.py
index 1d8d632210..db1a728a2e 100644
--- a/keystone/tests/unit/test_backend_ldap.py
+++ b/keystone/tests/unit/test_backend_ldap.py
@@ -1308,6 +1308,53 @@ class LDAPIdentity(BaseLDAPIdentity):
         self.assertEqual('junk1', user_refs[0]['name'])
         self.assertEqual('sn=junk1,dc=example,dc=com', user_refs[0]['dn'])
 
+    @mock.patch.object(common_ldap.KeystoneLDAPHandler, 'connect')
+    @mock.patch.object(common_ldap.KeystoneLDAPHandler, 'search_s')
+    @mock.patch.object(common_ldap.KeystoneLDAPHandler, 'simple_bind_s')
+    def test_filter_ldap_result_with_case_sensitive_attr(self,
+                                                         mock_simple_bind_s,
+                                                         mock_search_s,
+                                                         mock_connect):
+        # Mock the ldap search results to return user entries
+        # irrespective of lowercase and uppercase characters in
+        # ldap_result attribute keys e.g. {'Sn': ['junk1']} with
+        # user_name_attribute('sn')
+        mock_search_s.return_value = [(
+            'sn=junk1,dc=example,dc=com',
+            {
+                'cn': [uuid.uuid4().hex],
+                'email': [uuid.uuid4().hex],
+                'sN': ['junk1']
+            }
+        ),
+            (
+            'sn=junk1,dc=example,dc=com',
+            {
+                'cn': [uuid.uuid4().hex],
+                'email': [uuid.uuid4().hex],
+                'Sn': ['junk1']
+            }
+        ),
+            (
+            'sn=junk1,dc=example,dc=com',
+            {
+                'cn': [uuid.uuid4().hex],
+                'email': [uuid.uuid4().hex],
+                'sn': ['    ']
+            }
+        )
+        ]
+
+        user_api = identity.backends.ldap.UserApi(CONF)
+        user_refs = user_api.get_all()
+        # validate that keystone.identity.backends.ldap.common.BaseLdap.
+        # _filter_ldap_result_by_attr() method filtered the ldap query results
+        # whose name attribute keys having case insensitive characters.
+        self.assertEqual(2, len(user_refs))
+
+        self.assertEqual('junk1', user_refs[0]['name'])
+        self.assertEqual('sn=junk1,dc=example,dc=com', user_refs[0]['dn'])
+
     @mock.patch.object(common_ldap.BaseLdap, '_ldap_get')
     def test_user_enabled_attribute_handles_expired(self, mock_ldap_get):
         # If using 'passwordisexpired' as enabled attribute, and inverting it,
diff --git a/releasenotes/notes/bug-1753585-7e11213743754999.yaml b/releasenotes/notes/bug-1753585-7e11213743754999.yaml
new file mode 100644
index 0000000000..83b77a0bf7
--- /dev/null
+++ b/releasenotes/notes/bug-1753585-7e11213743754999.yaml
@@ -0,0 +1,6 @@
+---
+fixes:
+  - |
+    ['bug 1753585 <https://bugs.launchpad.net/keystone/+bug/1753585>'_]
+    LDAP attribute names are now matched case insensitively to comply with
+    LDAP implementations.
\ No newline at end of file