diff --git a/packages/backend/src/core/ReactionService.ts b/packages/backend/src/core/ReactionService.ts
index f0a2876450..062d64f46b 100644
--- a/packages/backend/src/core/ReactionService.ts
+++ b/packages/backend/src/core/ReactionService.ts
@@ -337,6 +337,7 @@ export class ReactionService {
 		//#endregion
 	}
 
+	// TODO: 廃止
 	/**
 	 * 文字列タイプのレガシーな形式のリアクションを現在の形式に変換しつつ、
 	 * データベース上には存在する「0個のリアクションがついている」という情報を削除する。
diff --git a/packages/backend/src/core/entities/NoteEntityService.ts b/packages/backend/src/core/entities/NoteEntityService.ts
index 65a47d7591..ddc7f0aa38 100644
--- a/packages/backend/src/core/entities/NoteEntityService.ts
+++ b/packages/backend/src/core/entities/NoteEntityService.ts
@@ -329,7 +329,7 @@ export class NoteEntityService implements OnModuleInit {
 			: this.meta.enableReactionsBuffering
 				? await this.reactionsBufferingService.get(note.id)
 				: { deltas: {}, pairs: [] };
-		const reactions = mergeReactions(note.reactions, bufferdReactions.deltas ?? {});
+		const reactions = mergeReactions(this.reactionService.convertLegacyReactions(note.reactions), bufferdReactions.deltas ?? {});
 		for (const [name, count] of Object.entries(reactions)) {
 			if (count <= 0) {
 				delete reactions[name];