diff --git a/src/misc/reaction-lib.ts b/src/misc/reaction-lib.ts
index ced90ce78f..3d5608ef33 100644
--- a/src/misc/reaction-lib.ts
+++ b/src/misc/reaction-lib.ts
@@ -15,7 +15,9 @@ const basic10: Record<string, string> = {
 	'🍮': 'pudding',
 };
 
-export async function getFallbackReaction(): Promise<string> {
+export async function getFallbackReaction(reaction?: string | null): Promise<string> {
+	if (reaction === '👎') return reaction;
+
 	const meta = await fetchMeta();
 	return  meta.useStarForReactionFallback ? 'star' : 'like';
 }
@@ -26,7 +28,7 @@ export async function toDbReaction(reaction?: string | null, enableEmoji = true)
 	// 既存の文字列リアクションはそのまま
 	if (Object.values(basic10).includes(reaction)) return reaction;
 
-	if (!enableEmoji) return await getFallbackReaction();
+	if (!enableEmoji) return await getFallbackReaction(reaction);
 
 	// Unicode絵文字
 	const match = emojiRegex.exec(reaction);
diff --git a/src/remote/activitypub/kernel/like.ts b/src/remote/activitypub/kernel/like.ts
index 23b4aedd15..23dad682e2 100644
--- a/src/remote/activitypub/kernel/like.ts
+++ b/src/remote/activitypub/kernel/like.ts
@@ -15,9 +15,10 @@ export default async (actor: IRemoteUser, activity: ILike) => {
 
 	const note = await Notes.findOne(noteId);
 	if (note == null) {
-		apLogger.warn(`Like activity recivied, but no such note: ${id}`, { id });
+		apLogger.warn(`${activity.type} activity recivied, but no such note: ${id}`, { id });
 		return;
 	}
 
-	await create(actor, note, activity._misskey_reaction);
+	const reaction = activity.type === 'Dislike' ? '👎' : activity._misskey_reaction || activity.content || activity.name;
+	await create(actor, note, reaction);
 };
diff --git a/src/remote/activitypub/kernel/undo/index.ts b/src/remote/activitypub/kernel/undo/index.ts
index f49f66cc69..6dfedf58e0 100644
--- a/src/remote/activitypub/kernel/undo/index.ts
+++ b/src/remote/activitypub/kernel/undo/index.ts
@@ -37,6 +37,8 @@ export default async (actor: IRemoteUser, activity: IUndo): Promise<void> => {
 			unblock(actor, object as IBlock);
 			break;
 		case 'Like':
+		case 'Dislike':
+		case 'EmojiReaction':
 			undoLike(actor, object as ILike);
 			break;
 		case 'Announce':
diff --git a/src/remote/activitypub/type.ts b/src/remote/activitypub/type.ts
index 62475faefc..55fa418cea 100644
--- a/src/remote/activitypub/type.ts
+++ b/src/remote/activitypub/type.ts
@@ -159,7 +159,7 @@ export interface IRemove extends IActivity {
 }
 
 export interface ILike extends IActivity {
-	type: 'Like';
+	type: 'Like' | 'Dislike' | 'EmojiReaction';
 	_misskey_reaction?: string;
 }
 
@@ -180,6 +180,6 @@ export const isAccept = (object: IObject): object is IAccept => object.type ===
 export const isReject = (object: IObject): object is IReject => object.type === 'Reject';
 export const isAdd = (object: IObject): object is IAdd => object.type === 'Add';
 export const isRemove = (object: IObject): object is IRemove => object.type === 'Remove';
-export const isLike = (object: IObject): object is ILike => object.type === 'Like';
+export const isLike = (object: IObject): object is ILike => object.type === 'Like' || object.type === 'Dislike' || object.type === 'EmojiReaction';
 export const isAnnounce = (object: IObject): object is IAnnounce => object.type === 'Announce';
 export const isBlock = (object: IObject): object is IBlock => object.type === 'Block';