diff --git a/frontend/src/pages/DatabaseSchema.tsx b/frontend/src/pages/DatabaseSchema.tsx
index cce08fd..da0dba2 100644
--- a/frontend/src/pages/DatabaseSchema.tsx
+++ b/frontend/src/pages/DatabaseSchema.tsx
@@ -430,6 +430,9 @@ export default function DatabaseSchema() {
               setSelectedDbId(e.target.value);
               setSelectedTables(new Set());
               setSearchQuery('');
+              // Clear canvas immediately on database change
+              setNodes([]);
+              setEdges([]);
             }}
             className="border border-gray-300 rounded-md px-3 py-1.5 text-sm bg-white focus:outline-none focus:ring-2 focus:ring-primary-500 min-w-48"
           >