diff --git a/packages/backend/src/core/activitypub/ApRendererService.ts b/packages/backend/src/core/activitypub/ApRendererService.ts
index 8251bc3b15..cbd5465945 100644
--- a/packages/backend/src/core/activitypub/ApRendererService.ts
+++ b/packages/backend/src/core/activitypub/ApRendererService.ts
@@ -839,10 +839,24 @@ export class ApRendererService {
 			poll = await this.pollsRepository.findOneBy({ noteId: note.id });
 		}
 
-		let apAppend = '';
+		const apAppend: Appender[] = [];
 
 		if (quote) {
-			apAppend += `\n\nRE: ${quote}`;
+			// Append quote link as `<br><br><span class="quote-inline">RE: <a href="...">...</a></span>`
+			// the claas name `quote-inline` is used in non-misskey clients for styling quote notes.
+			// For compatibility, the span part should be kept as possible.
+			apAppend.push((doc, body) => {
+				body.appendChild(doc.createElement('br'));
+				body.appendChild(doc.createElement('br'));
+				const span = doc.createElement('span');
+				span.className = 'quote-inline';
+				span.appendChild(doc.createTextNode('RE: '));
+				const link = doc.createElement('a');
+				link.setAttribute('href', quote);
+				link.textContent = quote;
+				span.appendChild(link);
+				body.appendChild(span);
+			});
 		}
 
 		let summary = note.cw === '' ? String.fromCharCode(0x200B) : note.cw;