diff --git a/manila/api/v2/share_networks.py b/manila/api/v2/share_networks.py
index be97ccd8bc..19cac03243 100644
--- a/manila/api/v2/share_networks.py
+++ b/manila/api/v2/share_networks.py
@@ -61,6 +61,10 @@ class ShareNetworkController(wsgi.Controller):
 
         return self._view_builder.build_share_network(req, share_network)
 
+    def _all_share_servers_are_auto_deletable(self, share_network):
+        return all([ss['is_auto_deletable'] for ss
+                    in share_network['share_servers']])
+
     def delete(self, req, id):
         """Delete specified share network."""
         context = req.environ['manila.context']
@@ -90,6 +94,16 @@ class ShareNetworkController(wsgi.Controller):
             LOG.error(msg)
             raise exc.HTTPConflict(explanation=msg)
 
+        # NOTE(silvacarlose): Do not allow the deletion of any share server
+        # if one of them has the flag is_auto_deletable = False
+        if not self._all_share_servers_are_auto_deletable(share_network):
+            msg = _("The service cannot determine if there are any "
+                    "non-managed shares on the share network %(id)s, so it "
+                    "cannot be deleted. Please contact the cloud "
+                    "administrator to rectify.") % {'id': id}
+            LOG.error(msg)
+            raise exc.HTTPConflict(explanation=msg)
+
         for share_server in share_network['share_servers']:
             self.share_rpcapi.delete_share_server(context, share_server)
         db_api.share_network_delete(context, id)
diff --git a/manila/share/manager.py b/manila/share/manager.py
index 0542000666..75a00144fc 100644
--- a/manila/share/manager.py
+++ b/manila/share/manager.py
@@ -2605,6 +2605,17 @@ class ShareManager(manager.SchedulerDependentManager):
         if share_server and share_server['is_auto_deletable']:
             self.db.share_server_update(context, share_server['id'],
                                         {'is_auto_deletable': False})
+            msg = ("Since share %(share)s has been un-managed from share "
+                   "server %(server)s. This share server must be removed "
+                   "manually, either by un-managing or by deleting it. The "
+                   "share network %(network)s cannot be deleted unless this "
+                   "share server has been removed.")
+            msg_args = {
+                'share': share_id,
+                'server': share_server['id'],
+                'network': share_server['share_network_id']
+            }
+            LOG.warning(msg, msg_args)
 
         LOG.info("Share %s: unmanaged successfully.", share_id)
 
diff --git a/manila/tests/api/v2/test_share_networks.py b/manila/tests/api/v2/test_share_networks.py
index a08546a408..727088d7a4 100644
--- a/manila/tests/api/v2/test_share_networks.py
+++ b/manila/tests/api/v2/test_share_networks.py
@@ -211,6 +211,9 @@ class ShareNetworkAPITest(test.TestCase):
         self.mock_object(db_api, 'share_instances_get_all_by_share_network',
                          mock.Mock(return_value=[]))
         self.mock_object(self.controller.share_rpcapi, 'delete_share_server')
+        self.mock_object(self.controller,
+                         '_all_share_servers_are_auto_deletable',
+                         mock.Mock(return_value=True))
         self.mock_object(db_api, 'share_network_delete')
 
         self.controller.delete(self.req, share_nw['id'])
@@ -246,6 +249,9 @@ class ShareNetworkAPITest(test.TestCase):
                          mock.Mock(return_value=share_nw))
         self.mock_object(db_api, 'share_instances_get_all_by_share_network',
                          mock.Mock(return_value=[]))
+        self.mock_object(self.controller,
+                         '_all_share_servers_are_auto_deletable',
+                         mock.Mock(return_value=True))
         self.mock_object(self.controller.share_rpcapi, 'delete_share_server')
         self.mock_object(db_api, 'share_network_delete')
         self.mock_object(share_networks.QUOTAS, 'reserve',
@@ -307,6 +313,37 @@ class ShareNetworkAPITest(test.TestCase):
         db_api.share_network_get.assert_called_once_with(
             self.req.environ['manila.context'], share_nw['id'])
 
+    def test_delete_contains_is_auto_deletable_false_servers(self):
+        share_nw = fake_share_network.copy()
+        self.mock_object(db_api, 'share_network_get',
+                         mock.Mock(return_value=share_nw))
+        self.mock_object(db_api, 'count_share_groups_in_share_network')
+        self.mock_object(share_networks.ShareNetworkController,
+                         '_all_share_servers_are_auto_deletable',
+                         mock.Mock(return_value=False))
+
+        self.assertRaises(webob_exc.HTTPConflict,
+                          self.controller.delete,
+                          self.req,
+                          share_nw['id'])
+
+        db_api.share_network_get.assert_called_once_with(
+            self.req.environ['manila.context'], share_nw['id'])
+
+    @ddt.data(
+        ({'share_servers': [{'is_auto_deletable': True},
+                            {'is_auto_deletable': True}]}, True),
+        ({'share_servers': [{'is_auto_deletable': True},
+                            {'is_auto_deletable': False}]}, False),
+    )
+    @ddt.unpack
+    def test__share_servers_are_auto_deletable(self, fake_share_network,
+                                               expected_result):
+        self.assertEqual(
+            expected_result,
+            self.controller._all_share_servers_are_auto_deletable(
+                fake_share_network))
+
     def test_show_nominal(self):
         share_nw = 'fake network id'
         with mock.patch.object(db_api,