diff --git a/locales/index.d.ts b/locales/index.d.ts
index 114247b43..6ce0fee33 100644
--- a/locales/index.d.ts
+++ b/locales/index.d.ts
@@ -1113,6 +1113,8 @@ export interface Locale {
     "refreshing": string;
     "pullDownToRefresh": string;
     "disableStreamingTimeline": string;
+    "urlPreviewDenyList": string;
+    "urlPreviewDenyListDescription": string;
     "_announcement": {
         "forExistingUsers": string;
         "forExistingUsersDescription": string;
diff --git a/locales/ja-JP.yml b/locales/ja-JP.yml
index 907cbf0f5..ca678e305 100644
--- a/locales/ja-JP.yml
+++ b/locales/ja-JP.yml
@@ -1110,6 +1110,8 @@ releaseToRefresh: "離してリロード"
 refreshing: "リロード中"
 pullDownToRefresh: "引っ張ってリロード"
 disableStreamingTimeline: "タイムラインのリアルタイム更新を無効にする"
+urlPreviewDenyList: "サムネイルの表示を制限するURL"
+urlPreviewDenyListDescription: "スペースで区切るとAND指定になり、改行で区切るとOR指定になります。スラッシュで囲むと正規表現になります。一致した場合、サムネイルがぼかされて表示されます。"
 
 _announcement:
   forExistingUsers: "既存ユーザーのみ"
diff --git a/packages/backend/migration/1699284486293-urlPreviewDenyList.js b/packages/backend/migration/1699284486293-urlPreviewDenyList.js
new file mode 100644
index 000000000..4b921ad57
--- /dev/null
+++ b/packages/backend/migration/1699284486293-urlPreviewDenyList.js
@@ -0,0 +1,16 @@
+/*
+ * SPDX-FileCopyrightText: syuilo and other misskey contributors
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+export class UrlPreviewDenyList1699284486293 {
+    name = 'UrlPreviewDenyList1699284486293'
+
+    async up(queryRunner) {
+        await queryRunner.query(`ALTER TABLE "meta" ADD "urlPreviewDenyList" character varying(3072) array NOT NULL DEFAULT '{}'`);
+    }
+
+    async down(queryRunner) {
+        await queryRunner.query(`ALTER TABLE "meta" DROP COLUMN "urlPreviewDenyList"`);
+    }
+}
diff --git a/packages/backend/src/models/entities/Meta.ts b/packages/backend/src/models/entities/Meta.ts
index 6015296a2..58251430b 100644
--- a/packages/backend/src/models/entities/Meta.ts
+++ b/packages/backend/src/models/entities/Meta.ts
@@ -468,4 +468,9 @@ export class MiMeta {
 		default: 300,
 	})
 	public perUserListTimelineCacheMax: number;
+
+	@Column('varchar', {
+		length: 3072, array: true, default: '{}',
+	})
+	public urlPreviewDenyList: string[];
 }
diff --git a/packages/backend/src/server/api/endpoints/admin/meta.ts b/packages/backend/src/server/api/endpoints/admin/meta.ts
index d4da22e1a..7d0ea6595 100644
--- a/packages/backend/src/server/api/endpoints/admin/meta.ts
+++ b/packages/backend/src/server/api/endpoints/admin/meta.ts
@@ -298,6 +298,14 @@ export const meta = {
 				type: 'number',
 				optional: false, nullable: false,
 			},
+			urlPreviewDenyList: {
+				type: 'array',
+				optional: true, nullable: false,
+				items: {
+					type: 'string',
+					optional: false, nullable: false,
+				},
+			},
 		},
 	},
 } as const;
@@ -404,6 +412,7 @@ export default class extends Endpoint<typeof meta, typeof paramDef> {
 				perRemoteUserUserTimelineCacheMax: instance.perRemoteUserUserTimelineCacheMax,
 				perUserHomeTimelineCacheMax: instance.perUserHomeTimelineCacheMax,
 				perUserListTimelineCacheMax: instance.perUserListTimelineCacheMax,
+				urlPreviewDenyList: instance.urlPreviewDenyList,
 			};
 		});
 	}
diff --git a/packages/backend/src/server/api/endpoints/admin/update-meta.ts b/packages/backend/src/server/api/endpoints/admin/update-meta.ts
index 5d5812ff3..f94b8d3ba 100644
--- a/packages/backend/src/server/api/endpoints/admin/update-meta.ts
+++ b/packages/backend/src/server/api/endpoints/admin/update-meta.ts
@@ -110,6 +110,9 @@ export const paramDef = {
 		perRemoteUserUserTimelineCacheMax: { type: 'integer' },
 		perUserHomeTimelineCacheMax: { type: 'integer' },
 		perUserListTimelineCacheMax: { type: 'integer' },
+		urlPreviewDenyList: { type: 'array', nullable: true, items: {
+			type: 'string',
+		} },
 	},
 	required: [],
 } as const;
@@ -147,6 +150,10 @@ export default class extends Endpoint<typeof meta, typeof paramDef> {
 				set.sensitiveWords = ps.sensitiveWords.filter(Boolean);
 			}
 
+			if (Array.isArray(ps.urlPreviewDenyList)) {
+				set.urlPreviewDenyList = ps.urlPreviewDenyList.filter(Boolean);
+			}
+
 			if (ps.themeColor !== undefined) {
 				set.themeColor = ps.themeColor;
 			}
diff --git a/packages/backend/src/server/web/UrlPreviewService.ts b/packages/backend/src/server/web/UrlPreviewService.ts
index d590244e3..76e847b7c 100644
--- a/packages/backend/src/server/web/UrlPreviewService.ts
+++ b/packages/backend/src/server/web/UrlPreviewService.ts
@@ -5,6 +5,7 @@
 
 import { Inject, Injectable } from '@nestjs/common';
 import { summaly } from 'summaly';
+import RE2 from 're2';
 import { DI } from '@/di-symbols.js';
 import type { Config } from '@/config.js';
 import { MetaService } from '@/core/MetaService.js';
@@ -94,6 +95,23 @@ export class UrlPreviewService {
 			summary.icon = this.wrap(summary.icon);
 			summary.thumbnail = this.wrap(summary.thumbnail);
 
+			const includeDenyList = meta.urlPreviewDenyList.some(filter => {
+				// represents RegExp
+				const regexp = /^\/(.+)\/(.*)$/.exec(filter);
+				// This should never happen due to input sanitisation.
+				if (!regexp) {
+					const words = filter.split(' ');
+					return words.every(keyword => summary.url.includes(keyword));
+				}
+				try {
+					return new RE2(regexp[1], regexp[2]).test(summary.url);
+				} catch (err) {
+					// This should never happen due to input sanitisation.
+					return false;
+				}
+			});
+			if (includeDenyList) summary.sensitive = true;
+
 			// Cache 7days
 			reply.header('Cache-Control', 'max-age=604800, immutable');
 
diff --git a/packages/frontend/src/components/MkUrlPreview.vue b/packages/frontend/src/components/MkUrlPreview.vue
index 19bbb3882..a40957786 100644
--- a/packages/frontend/src/components/MkUrlPreview.vue
+++ b/packages/frontend/src/components/MkUrlPreview.vue
@@ -45,7 +45,7 @@ SPDX-License-Identifier: AGPL-3.0-only
 </template>
 <div v-else>
 	<component :is="self ? 'MkA' : 'a'" :class="[$style.link, { [$style.compact]: compact }]" :[attr]="self ? url.substring(local.length) : url" rel="nofollow noopener" :target="target" :title="url">
-		<div v-if="thumbnail" :class="$style.thumbnail" :style="`background-image: url('${thumbnail}')`">
+		<div v-if="thumbnail" :class="[$style.thumbnail, { [$style.thumbnailBlur]: sensitive }]" :style="`background-image: url('${thumbnail}')`">
 		</div>
 		<article :class="$style.body">
 			<header :class="$style.header">
@@ -118,6 +118,7 @@ let description = $ref<string | null>(null);
 let thumbnail = $ref<string | null>(null);
 let icon = $ref<string | null>(null);
 let sitename = $ref<string | null>(null);
+let sensitive = $ref<boolean | undefined>(undefined);
 let player = $ref({
 	url: null,
 	width: null,
@@ -170,6 +171,7 @@ window.fetch(`/url?url=${encodeURIComponent(requestUrl.href)}&lang=${versatileLa
 		icon = info.icon;
 		sitename = info.sitename;
 		player = info.player;
+		sensitive = info.sensitive;
 	});
 
 function adjustTweetHeight(message: any) {
@@ -319,6 +321,10 @@ onUnmounted(() => {
 	margin-top: 6px;
 }
 
+.thumbnailBlur {
+		filter: blur(8px);
+}
+
 @container (max-width: 400px) {
 	.link {
 		font-size: 12px;
diff --git a/packages/frontend/src/pages/admin/moderation.vue b/packages/frontend/src/pages/admin/moderation.vue
index 313d8412b..95ab3b5b3 100644
--- a/packages/frontend/src/pages/admin/moderation.vue
+++ b/packages/frontend/src/pages/admin/moderation.vue
@@ -34,6 +34,11 @@ SPDX-License-Identifier: AGPL-3.0-only
 						<template #label>{{ i18n.ts.sensitiveWords }}</template>
 						<template #caption>{{ i18n.ts.sensitiveWordsDescription }}<br>{{ i18n.ts.sensitiveWordsDescription2 }}</template>
 					</MkTextarea>
+
+					<MkTextarea v-model="urlPreviewDenyList">
+						<template #label>{{ i18n.ts.urlPreviewDenyList }}</template>
+						<template #caption>{{ i18n.ts.urlPreviewDenyListDescription }}</template>
+					</MkTextarea>
 				</div>
 			</FormSuspense>
 		</MkSpacer>
@@ -69,6 +74,7 @@ let emailRequiredForSignup: boolean = $ref(false);
 let sensitiveWords: string = $ref('');
 let preservedUsernames: string = $ref('');
 let tosUrl: string | null = $ref(null);
+let urlPreviewDenyList: string = $ref('');
 
 async function init() {
 	const meta = await os.api('admin/meta');
@@ -77,6 +83,7 @@ async function init() {
 	sensitiveWords = meta.sensitiveWords.join('\n');
 	preservedUsernames = meta.preservedUsernames.join('\n');
 	tosUrl = meta.tosUrl;
+	urlPreviewDenyList = meta.urlPreviewDenyList.join('\n');
 }
 
 function save() {
@@ -86,6 +93,7 @@ function save() {
 		tosUrl,
 		sensitiveWords: sensitiveWords.split('\n'),
 		preservedUsernames: preservedUsernames.split('\n'),
+		urlPreviewDenyList: urlPreviewDenyList.split('\n'),
 	}).then(() => {
 		fetchInstance();
 	});
diff --git a/packages/misskey-js/etc/misskey-js.api.md b/packages/misskey-js/etc/misskey-js.api.md
index c6084ce2c..76bb34d97 100644
--- a/packages/misskey-js/etc/misskey-js.api.md
+++ b/packages/misskey-js/etc/misskey-js.api.md
@@ -20,6 +20,7 @@ type Ad = TODO_2;
 // @public (undocumented)
 type AdminInstanceMetadata = DetailedInstanceMetadata & {
     blockedHosts: string[];
+    urlPreviewDenyList: string[];
 };
 
 // @public (undocumented)
diff --git a/packages/misskey-js/src/entities.ts b/packages/misskey-js/src/entities.ts
index d61e4204b..b09fd0170 100644
--- a/packages/misskey-js/src/entities.ts
+++ b/packages/misskey-js/src/entities.ts
@@ -355,6 +355,7 @@ export type InstanceMetadata = LiteInstanceMetadata | DetailedInstanceMetadata;
 export type AdminInstanceMetadata = DetailedInstanceMetadata & {
 	// TODO: There are more fields.
 	blockedHosts: string[];
+	urlPreviewDenyList: string[];
 };
 
 export type ServerInfo = {