diff --git a/packages/gitbook/src/components/DocumentView/Mention.tsx b/packages/gitbook/src/components/DocumentView/Mention.tsx
index 7d4db5178..a920cd1a6 100644
--- a/packages/gitbook/src/components/DocumentView/Mention.tsx
+++ b/packages/gitbook/src/components/DocumentView/Mention.tsx
@@ -15,7 +15,7 @@ export async function Mention(props: InlineProps<DocumentInlineMention>) {
         : null;
 
     if (!resolved) {
-        return null;
+        return <span className="underline">Broken link</span>;
     }
 
     return (