diff --git a/lib/NGCP/Panel/Controller/API/ContactsItem.pm b/lib/NGCP/Panel/Controller/API/ContactsItem.pm
index 6f5466317d..9b679f0a8a 100644
--- a/lib/NGCP/Panel/Controller/API/ContactsItem.pm
+++ b/lib/NGCP/Panel/Controller/API/ContactsItem.pm
@@ -323,7 +323,15 @@ sub DELETE :Allow {
     {
         my $contact = $self->contact_by_id($c, $id);
         last unless $self->resource_exists($c, contact => $contact);
-        $contact->delete;
+        my $contract_count = $c->model('DB')->resultset('contracts')->search({
+            contact_id => $id
+        });
+        if($contract_count > 0) {
+            $self->error($c, HTTP_LOCKED, "Contact is still in use.");
+            last;
+        } else {
+            $contact->delete;
+        }
         $guard->commit;
 
         $c->cache->remove($c->request->uri->canonical->as_string);
diff --git a/t/api-contacts.t b/t/api-contacts.t
index 6a7623b7b1..7bd8d4b63f 100644
--- a/t/api-contacts.t
+++ b/t/api-contacts.t
@@ -244,6 +244,9 @@ my @allcontacts = ();
         $res = $ua->request($req);
         ok($res->code == 204, "check delete of contact");
     }
+    $req = HTTP::Request->new('DELETE', $uri.'/api/contacts/1');
+    $res = $ua->request($req);
+    ok($res->code == 423, "check delete of used contact");
 }
 
 done_testing;