diff --git a/src/chart/federation.ts b/src/chart/federation.ts
new file mode 100644
index 000000000..9d5830a53
--- /dev/null
+++ b/src/chart/federation.ts
@@ -0,0 +1,65 @@
+import autobind from 'autobind-decorator';
+import Chart, { Obj } from '.';
+
+/**
+ * フェデレーションに関するチャート
+ */
+type FederationLog = {
+	instance: {
+		/**
+		 * インスタンス数の合計
+		 */
+		total: number;
+
+		/**
+		 * 増加インスタンス数
+		 */
+		inc: number;
+
+		/**
+		 * 減少インスタンス数
+		 */
+		dec: number;
+	};
+};
+
+class FederationChart extends Chart<FederationLog> {
+	constructor() {
+		super('federation');
+	}
+
+	@autobind
+	protected async getTemplate(init: boolean, latest?: FederationLog): Promise<FederationLog> {
+		const [total] = init ? await Promise.all([
+			Instance.count({})
+		]) : [
+			latest ? latest.instance.total : 0
+		];
+
+		return {
+			instance: {
+				total: total,
+				inc: 0,
+				dec: 0
+			}
+		};
+	}
+
+	@autobind
+	public async update(isAdditional: boolean) {
+		const update: Obj = {};
+
+		update.total = isAdditional ? 1 : -1;
+		if (isAdditional) {
+			update.inc = 1;
+		} else {
+			update.dec = 1;
+		}
+
+		await this.inc({
+			instance: update
+		});
+	}
+}
+
+export default new FederationChart();
diff --git a/src/models/instance.ts b/src/models/instance.ts
new file mode 100644
index 000000000..d3906df42
--- /dev/null
+++ b/src/models/instance.ts
@@ -0,0 +1,35 @@
+import * as mongo from 'mongodb';
+import db from '../db/mongodb';
+
+const Instance = db.get<IInstance>('instances');
+Instance.createIndex('host', { unique: true });
+export default Instance;
+
+export interface IInstance {
+	_id: mongo.ObjectID;
+
+	/**
+	 * ホスト
+	 */
+	host: string;
+
+	/**
+	 * このインスタンスを捕捉した日時
+	 */
+	caughtAt: Date;
+
+	/**
+	 * このインスタンスのシステム (MastodonとかMisskeyとかPleromaとか)
+	 */
+	system: string;
+
+	/**
+	 * このインスタンスのユーザー数
+	 */
+	usersCount: number;
+
+	/**
+	 * このインスタンスから受け取った投稿数
+	 */
+	notesCount: number;
+}
diff --git a/src/remote/activitypub/models/person.ts b/src/remote/activitypub/models/person.ts
index a39c8d33c..f115dee87 100644
--- a/src/remote/activitypub/models/person.ts
+++ b/src/remote/activitypub/models/person.ts
@@ -13,6 +13,8 @@ import htmlToMFM from '../../../mfm/html-to-mfm';
 import usersChart from '../../../chart/users';
 import { URL } from 'url';
 import { resolveNote } from './note';
+import registerInstance from '../../../services/register-instance';
+import Instance from '../../../models/instance';
 
 const log = debug('misskey:activitypub');
 
@@ -173,6 +175,18 @@ export async function createPerson(uri: string, resolver?: Resolver): Promise<IU
 		throw e;
 	}
 
+	// Register host
+	registerInstance(host).then(i => {
+		Instance.update({ _id: i._id }, {
+			$inc: {
+				usersCount: 1
+			}
+		});
+
+		// TODO
+		//perInstanceChart.newUser();
+	});
+
 	//#region Increment users count
 	Meta.update({}, {
 		$inc: {
@@ -214,6 +228,7 @@ export async function createPerson(uri: string, resolver?: Resolver): Promise<IU
 	//#endregion
 
 	await updateFeatured(user._id).catch(err => console.log(err));
+
 	return user;
 }
 
diff --git a/src/services/note/create.ts b/src/services/note/create.ts
index 401543b48..96ffe9687 100644
--- a/src/services/note/create.ts
+++ b/src/services/note/create.ts
@@ -28,6 +28,8 @@ import perUserNotesChart from '../../chart/per-user-notes';
 
 import { erase, unique } from '../../prelude/array';
 import insertNoteUnread from './unread';
+import registerInstance from '../register-instance';
+import Instance from '../../models/instance';
 
 type NotificationType = 'reply' | 'renote' | 'quote' | 'mention';
 
@@ -170,6 +172,20 @@ export default async (user: IUser, data: Option, silent = false) => new Promise<
 	notesChart.update(note, true);
 	perUserNotesChart.update(user, note, true);
 
+	// Register host
+	if (isRemoteUser(user)) {
+		registerInstance(user.host).then(i => {
+			Instance.update({ _id: i._id }, {
+				$inc: {
+					notesCount: 1
+				}
+			});
+
+			// TODO
+			//perInstanceChart.newNote();
+		});
+	}
+
 	// ハッシュタグ登録
 	tags.map(tag => registerHashtag(user, tag));
 
diff --git a/src/services/register-instance.ts b/src/services/register-instance.ts
new file mode 100644
index 000000000..6576a9ed0
--- /dev/null
+++ b/src/services/register-instance.ts
@@ -0,0 +1,22 @@
+import Instance, { IInstance } from '../models/instance';
+import federationChart from '../chart/federation';
+
+export default async function(host: string): Promise<IInstance> {
+	if (host == null) return null;
+
+	const index = await Instance.findOne({ host });
+
+	if (index == null) {
+		const i = await Instance.insert({
+			host,
+			caughtAt: new Date(),
+			system: null // TODO
+		});
+
+		federationChart.update(true);
+
+		return i;
+	} else {
+		return index;
+	}
+}