diff --git a/gunicorn/workers/gthread.py b/gunicorn/workers/gthread.py
index fcdcc7a7..f9281588 100644
--- a/gunicorn/workers/gthread.py
+++ b/gunicorn/workers/gthread.py
@@ -243,6 +243,7 @@ class ThreadWorker(base.Worker):
 
     def finish_request(self, fs):
         if fs.cancelled():
+            self.nr_conns -= 1
             fs.conn.close()
             return