diff --git a/src/index.mjs b/src/index.mjs
index fcc4f18..fdc809e 100644
--- a/src/index.mjs
+++ b/src/index.mjs
@@ -63,7 +63,10 @@ async function ghActionBot() {
       }
 
       // filter on label
-      if (!PULL_LABEL_FILTER.split(',').every(label => pull.labels.includes(label))) {
+      if (
+        PULL_LABEL_FILTER &&
+        !PULL_LABEL_FILTER.split(',').every(label => pull.labels.includes(label))
+      ) {
         logger.debug(
           `SKIP PULL #${
             pull.number