diff --git a/packages/backend/src/server/api/mastodon/converters/announcement.ts b/packages/backend/src/server/api/mastodon/converters/announcement.ts
new file mode 100644
index 000000000..9b5445cef
--- /dev/null
+++ b/packages/backend/src/server/api/mastodon/converters/announcement.ts
@@ -0,0 +1,27 @@
+import { Announcement } from "@/models/entities/announcement.js";
+import { ILocalUser } from "@/models/entities/user.js";
+import { awaitAll } from "@/prelude/await-all";
+import { AnnouncementReads } from "@/models/index.js";
+import { MfmHelpers } from "@/server/api/mastodon/helpers/mfm.js";
+import mfm from "mfm-js";
+
+export class AnnouncementConverter {
+    public static encode(announcement: Announcement, isRead: boolean): MastodonEntity.Announcement {
+        return {
+            id: announcement.id,
+            content: `<h1>${MfmHelpers.toHtml(mfm.parse(announcement.title), []) ?? 'Announcement'}</h1>${MfmHelpers.toHtml(mfm.parse(announcement.text), []) ?? ''}`,
+            starts_at: null,
+            ends_at: null,
+            published: true,
+            all_day: false,
+            published_at: announcement.createdAt.toISOString(),
+            updated_at: announcement.updatedAt?.toISOString() ?? announcement.createdAt.toISOString(),
+            read: isRead,
+            mentions: [], //FIXME
+            statuses: [],
+            tags: [],
+            emojis: [], //FIXME
+            reactions: [],
+        };
+    }
+}
\ No newline at end of file
diff --git a/packages/backend/src/server/api/mastodon/endpoints/misc.ts b/packages/backend/src/server/api/mastodon/endpoints/misc.ts
index 5e157c0cd..0f47aa7b9 100644
--- a/packages/backend/src/server/api/mastodon/endpoints/misc.ts
+++ b/packages/backend/src/server/api/mastodon/endpoints/misc.ts
@@ -1,8 +1,11 @@
 import Router from "@koa/router";
 import { getClient } from "@/server/api/mastodon/index.js";
-import { convertId, IdType } from "@/misc/convert-id.js";
-import { convertAnnouncementId } from "@/server/api/mastodon/converters.js";
 import { MiscHelpers } from "@/server/api/mastodon/helpers/misc.js";
+import authenticate from "@/server/api/authenticate.js";
+import { argsToBools } from "@/server/api/mastodon/endpoints/timeline.js";
+import { Announcements } from "@/models/index.js";
+import { convertAnnouncementId } from "@/server/api/mastodon/converters.js";
+import { convertId, IdType } from "@/misc/convert-id.js";
 
 export function setupEndpointsMisc(router: Router): void {
     router.get("/v1/custom_emojis", async (ctx) => {
@@ -30,36 +33,49 @@ export function setupEndpointsMisc(router: Router): void {
     });
 
     router.get("/v1/announcements", async (ctx) => {
-        const BASE_URL = `${ctx.request.protocol}://${ctx.request.hostname}`;
-        const accessTokens = ctx.request.headers.authorization;
-        const client = getClient(BASE_URL, accessTokens);
         try {
-            const data = await client.getInstanceAnnouncements();
-            ctx.body = data.data.map((announcement) =>
-                convertAnnouncementId(announcement),
-            );
+            const auth = await authenticate(ctx.headers.authorization, null);
+            const user = auth[0] ?? null;
+
+            if (!user) {
+                ctx.status = 401;
+                return;
+            }
+
+            const args = argsToBools(ctx.query, ['with_dismissed']);
+            ctx.body = await MiscHelpers.getAnnouncements(user, args['with_dismissed'])
+                .then(p => p.map(x => convertAnnouncementId(x)));
         } catch (e: any) {
-            console.error(e);
-            ctx.status = 401;
-            ctx.body = e.response.data;
+            ctx.status = 500;
+            ctx.body = { error: e.message };
         }
     });
 
     router.post<{ Params: { id: string } }>(
         "/v1/announcements/:id/dismiss",
         async (ctx) => {
-            const BASE_URL = `${ctx.request.protocol}://${ctx.request.hostname}`;
-            const accessTokens = ctx.request.headers.authorization;
-            const client = getClient(BASE_URL, accessTokens);
             try {
-                const data = await client.dismissInstanceAnnouncement(
-                    convertId(ctx.params.id, IdType.IceshrimpId),
-                );
-                ctx.body = data.data;
+                const auth = await authenticate(ctx.headers.authorization, null);
+                const user = auth[0] ?? null;
+
+                if (!user) {
+                    ctx.status = 401;
+                    return;
+                }
+
+                const id = convertId(ctx.params.id, IdType.IceshrimpId);
+                const announcement = await Announcements.findOneBy({id: id});
+
+                if (!announcement) {
+                    ctx.status = 404;
+                    return;
+                }
+
+                await MiscHelpers.dismissAnnouncement(announcement, user);
+                ctx.body = {};
             } catch (e: any) {
-                console.error(e);
-                ctx.status = 401;
-                ctx.body = e.response.data;
+                ctx.status = 500;
+                ctx.body = { error: e.message };
             }
         },
     );
diff --git a/packages/backend/src/server/api/mastodon/helpers/misc.ts b/packages/backend/src/server/api/mastodon/helpers/misc.ts
index 51666b68c..acefa9d4f 100644
--- a/packages/backend/src/server/api/mastodon/helpers/misc.ts
+++ b/packages/backend/src/server/api/mastodon/helpers/misc.ts
@@ -1,11 +1,15 @@
 import config from "@/config/index.js";
 import { FILE_TYPE_BROWSERSAFE, MAX_NOTE_TEXT_LENGTH } from "@/const.js";
 import { fetchMeta } from "@/misc/fetch-meta.js";
-import { Instances, Notes, Users } from "@/models/index.js";
+import { AnnouncementReads, Announcements, Instances, Notes, Users } from "@/models/index.js";
 import { IsNull } from "typeorm";
 import { awaitAll } from "@/prelude/await-all.js";
 import { UserConverter } from "@/server/api/mastodon/converters/user.js";
 import { convertAccountId } from "@/server/api/mastodon/converters.js";
+import { Announcement } from "@/models/entities/announcement.js";
+import { ILocalUser } from "@/models/entities/user.js";
+import { AnnouncementConverter } from "@/server/api/mastodon/converters/announcement.js";
+import { genId } from "@/misc/gen-id.js";
 
 export class MiscHelpers {
     public static async getInstance(): Promise<MastodonEntity.Instance> {
@@ -81,4 +85,42 @@ export class MiscHelpers {
 
         return awaitAll(res);
     }
+
+    public static async getAnnouncements(user: ILocalUser, includeRead: boolean = false): Promise<MastodonEntity.Announcement[]> {
+        if (includeRead) {
+            const [announcements, reads] = await Promise.all([
+                Announcements.createQueryBuilder("announcement")
+                    .orderBy({"announcement.id": "DESC"})
+                    .getMany(),
+                AnnouncementReads.findBy({userId: user.id})
+                    .then(p => p.map(x => x.announcementId))
+            ]);
+
+            return announcements.map(p => AnnouncementConverter.encode(p, reads.includes(p.id)));
+        }
+
+        const sq = AnnouncementReads.createQueryBuilder("reads")
+            .select("reads.announcementId")
+            .where("reads.userId = :userId");
+
+        const query = Announcements.createQueryBuilder("announcement")
+            .where(`announcement.id NOT IN (${sq.getQuery()})`)
+            .orderBy({"announcement.id": "DESC"})
+            .setParameter("userId", user.id);
+
+        return query.getMany()
+            .then(p => p.map(x => AnnouncementConverter.encode(x, false)));
+    }
+
+    public static async dismissAnnouncement(announcement: Announcement, user: ILocalUser): Promise<void> {
+        const exists = await AnnouncementReads.exist({where: {userId: user.id, announcementId: announcement.id}});
+        if (!exists) {
+            await AnnouncementReads.insert({
+                id: genId(),
+                createdAt: new Date(),
+                userId: user.id,
+                announcementId: announcement.id
+            });
+        }
+    }
 }
\ No newline at end of file