diff --git a/test/tests/shared-functions.bash b/test/tests/shared-functions.bash
index bd55baf..37814e6 100644
--- a/test/tests/shared-functions.bash
+++ b/test/tests/shared-functions.bash
@@ -11,6 +11,7 @@ function unset_n_env(){
   unset N_NODE_MIRROR
   unset N_NODE_DOWNLOAD_MIRROR
   unset N_MAX_REMOTE_MATCHES
+  unset N_PRESERVE_NPM
   unset HTTP_USER
   unset HTTP_PASSWORD
 }