diff --git a/src/static/js/ace2_inner.js b/src/static/js/ace2_inner.js
index 490eee19..07580faa 100644
--- a/src/static/js/ace2_inner.js
+++ b/src/static/js/ace2_inner.js
@@ -3514,6 +3514,13 @@ function Ace2Inner(){
     var keyCode = evt.keyCode;
     var which = evt.which;
 
+    // prevent ESC key
+    if (keyCode == 27)
+    {
+      evt.preventDefault();
+      return;
+    }
+
     //dmesg("keyevent type: "+type+", which: "+which);
     // Don't take action based on modifier keys going up and down.
     // Modifier keys do not generate "keypress" events.