diff --git a/test/plugin/test_in_tail.rb b/test/plugin/test_in_tail.rb
index f9b23580a7..36abb25a6c 100644
--- a/test/plugin/test_in_tail.rb
+++ b/test/plugin/test_in_tail.rb
@@ -21,6 +21,7 @@ def teardown
     super
     cleanup_directory(TMP_DIR)
     Fluent::Engine.stop
+    Timecop.return
   end
 
   def cleanup_directory(path)