diff --git a/superset-frontend/src/SqlLab/main.less b/superset-frontend/src/SqlLab/main.less
index 8f259f9f620..957677a86b3 100644
--- a/superset-frontend/src/SqlLab/main.less
+++ b/superset-frontend/src/SqlLab/main.less
@@ -423,7 +423,9 @@ div.tablePopover {
   font-family: @font-family-monospace;
 
   &.ace_autocomplete {
-    width: 520px;
+    // Use !important because Ace Editor applies extra CSS at the last second
+    // when opening the autocomplete.
+    width: 520px !important;
   }
 }