diff --git a/package.json b/package.json
index 880595e323ab..485fafc252d3 100644
--- a/package.json
+++ b/package.json
@@ -73,6 +73,7 @@
 		"@types/parse5": "6.0.0",
 		"@types/parsimmon": "1.10.6",
 		"@types/pug": "2.0.4",
+		"@types/punycode": "2.1.0",
 		"@types/qrcode": "1.4.0",
 		"@types/ratelimiter": "3.4.1",
 		"@types/redis": "2.8.28",
diff --git a/src/client/app/admin/views/instance.vue b/src/client/app/admin/views/instance.vue
index b11ee2dae68d..a657c0c8f3c8 100644
--- a/src/client/app/admin/views/instance.vue
+++ b/src/client/app/admin/views/instance.vue
@@ -133,7 +133,7 @@
 import Vue from 'vue';
 import i18n from '../../i18n';
 import { url, host } from '../../config';
-import { toUnicode } from 'punycode';
+import { toUnicode } from 'punycode/';
 import { faHeadset, faShieldAlt, faGhost, faUserPlus, faBolt } from '@fortawesome/free-solid-svg-icons';
 import { faEnvelope as farEnvelope } from '@fortawesome/free-regular-svg-icons';
 
diff --git a/src/client/app/common/views/components/acct.vue b/src/client/app/common/views/components/acct.vue
index f4e7a748c3a7..9c29bcc824d6 100644
--- a/src/client/app/common/views/components/acct.vue
+++ b/src/client/app/common/views/components/acct.vue
@@ -11,7 +11,7 @@
 <script lang="ts">
 import Vue from 'vue';
 import { host } from '../../../config';
-import { toUnicode } from 'punycode';
+import { toUnicode } from 'punycode/';
 export default Vue.extend({
 	props: ['user', 'detail'],
 	data() {
diff --git a/src/client/app/common/views/components/mention.vue b/src/client/app/common/views/components/mention.vue
index fec38f4e73b6..5aec1df07081 100644
--- a/src/client/app/common/views/components/mention.vue
+++ b/src/client/app/common/views/components/mention.vue
@@ -12,7 +12,7 @@
 <script lang="ts">
 import Vue from 'vue';
 import i18n from '../../../i18n';
-import { toUnicode } from 'punycode';
+import { toUnicode } from 'punycode/';
 import { host as localHost } from '../../../config';
 
 export default Vue.extend({
diff --git a/src/client/app/common/views/components/settings/profile.vue b/src/client/app/common/views/components/settings/profile.vue
index 0b1af965f2d3..111ba8f1a1ee 100644
--- a/src/client/app/common/views/components/settings/profile.vue
+++ b/src/client/app/common/views/components/settings/profile.vue
@@ -145,7 +145,7 @@
 import Vue from 'vue';
 import i18n from '../../../../i18n';
 import { apiUrl, host } from '../../../../config';
-import { toUnicode } from 'punycode';
+import { toUnicode } from 'punycode/';
 import { unique } from '../../../../../../prelude/array';
 import { faDownload, faUpload, faUnlockAlt, faBoxes, faCogs } from '@fortawesome/free-solid-svg-icons';
 import { faSave, faEnvelope } from '@fortawesome/free-regular-svg-icons';
diff --git a/src/client/app/common/views/components/signin.vue b/src/client/app/common/views/components/signin.vue
index 477f25680ecc..4f61aa5569a8 100644
--- a/src/client/app/common/views/components/signin.vue
+++ b/src/client/app/common/views/components/signin.vue
@@ -25,7 +25,7 @@
 import Vue from 'vue';
 import i18n from '../../../i18n';
 import { apiUrl, host } from '../../../config';
-import { toUnicode } from 'punycode';
+import { toUnicode } from 'punycode/';
 
 export default Vue.extend({
 	i18n: i18n('common/views/components/signin.vue'),
diff --git a/src/client/app/common/views/components/signup.vue b/src/client/app/common/views/components/signup.vue
index d75de81708aa..457e2dc84de8 100644
--- a/src/client/app/common/views/components/signup.vue
+++ b/src/client/app/common/views/components/signup.vue
@@ -48,7 +48,7 @@ import Vue from 'vue';
 import i18n from '../../../i18n';
 const getPasswordStrength = require('syuilo-password-strength');
 import { host, url } from '../../../config';
-import { toUnicode } from 'punycode';
+import { toUnicode } from 'punycode/';
 
 export default Vue.extend({
 	i18n: i18n('common/views/components/signup.vue'),
diff --git a/src/client/app/common/views/components/url.vue b/src/client/app/common/views/components/url.vue
index d29e0ecc421b..ad849d9b90bd 100644
--- a/src/client/app/common/views/components/url.vue
+++ b/src/client/app/common/views/components/url.vue
@@ -12,7 +12,7 @@
 
 <script lang="ts">
 import Vue from 'vue';
-import { toUnicode as decodePunycode } from 'punycode';
+import { toUnicode as decodePunycode } from 'punycode/';
 
 export default Vue.extend({
 	props: ['url', 'rel', 'target', 'trim'],
diff --git a/src/client/app/common/views/directives/autocomplete.ts b/src/client/app/common/views/directives/autocomplete.ts
index 74fc09363677..29de167cbd0c 100644
--- a/src/client/app/common/views/directives/autocomplete.ts
+++ b/src/client/app/common/views/directives/autocomplete.ts
@@ -1,5 +1,5 @@
 import * as getCaretCoordinates from 'textarea-caret';
-import { toASCII } from 'punycode';
+import { toASCII } from 'punycode/';
 
 export default {
 	bind(el, binding, vn) {
diff --git a/src/client/app/desktop/views/components/post-form.vue b/src/client/app/desktop/views/components/post-form.vue
index 52c742ad817f..fd11743ccc2f 100644
--- a/src/client/app/desktop/views/components/post-form.vue
+++ b/src/client/app/desktop/views/components/post-form.vue
@@ -77,7 +77,7 @@ import MkVisibilityChooser from '../../../common/views/components/visibility-cho
 import XPostFormAttaches from '../../../common/views/components/post-form-attaches.vue';
 import XVisibilityIcon from '../../../common/views/components/visibility-icon.vue';
 import form from '../../../common/scripts/post-form';
-import { toASCII } from 'punycode';
+import { toASCII } from 'punycode/';
 import extractMentions from '../../../../../misc/extract-mentions';
 import { parseBasic } from '../../../../../mfm/parse';
 import { host } from '../../../config';
diff --git a/src/client/app/desktop/views/pages/welcome.vue b/src/client/app/desktop/views/pages/welcome.vue
index 9a7f4122e2b3..631003199d11 100644
--- a/src/client/app/desktop/views/pages/welcome.vue
+++ b/src/client/app/desktop/views/pages/welcome.vue
@@ -148,7 +148,7 @@ import Vue from 'vue';
 import i18n from '../../../i18n';
 import { host, constants } from '../../../config';
 import { concat } from '../../../../../prelude/array';
-import { toUnicode } from 'punycode';
+import { toUnicode } from 'punycode/';
 
 export default Vue.extend({
 	i18n: i18n('desktop/views/pages/welcome.vue'),
diff --git a/src/client/app/mobile/views/components/post-form.vue b/src/client/app/mobile/views/components/post-form.vue
index 683ece09c326..9cb9ef69f814 100644
--- a/src/client/app/mobile/views/components/post-form.vue
+++ b/src/client/app/mobile/views/components/post-form.vue
@@ -72,7 +72,7 @@ import Vue from 'vue';
 import i18n from '../../../i18n';
 import { parseBasic } from '../../../../../mfm/parse';
 import { host } from '../../../config';
-import { toASCII } from 'punycode';
+import { toASCII } from 'punycode/';
 import extractMentions from '../../../../../misc/extract-mentions';
 import XPostFormAttaches from '../../../common/views/components/post-form-attaches.vue';
 import XVisibilityIcon from '../../../common/views/components/visibility-icon.vue';
diff --git a/src/client/app/mobile/views/pages/welcome.vue b/src/client/app/mobile/views/pages/welcome.vue
index 284f115dae16..d5f41a757178 100644
--- a/src/client/app/mobile/views/pages/welcome.vue
+++ b/src/client/app/mobile/views/pages/welcome.vue
@@ -47,7 +47,7 @@ import Vue from 'vue';
 import i18n from '../../../i18n';
 import { constants, host } from '../../../config';
 import { concat } from '../../../../../prelude/array';
-import { toUnicode } from 'punycode';
+import { toUnicode } from 'punycode/';
 
 export default Vue.extend({
 	i18n: i18n('mobile/views/pages/welcome.vue'),
diff --git a/src/mfm/language.ts b/src/mfm/language.ts
index 98bda94c18bf..56b7160d27ad 100644
--- a/src/mfm/language.ts
+++ b/src/mfm/language.ts
@@ -2,7 +2,7 @@ import * as P from 'parsimmon';
 import { createLeaf, createTree, urlRegex } from './prelude';
 import { Predicate } from '../prelude/relation';
 import parseAcct from '../misc/acct/parse';
-import { toUnicode } from 'punycode';
+import { toUnicode } from 'punycode/';
 import { emojiRegex, vendorEmojiRegex, localEmojiRegex } from '../misc/emoji-regex';
 
 export function removeOrphanedBrackets(s: string): string {
diff --git a/src/misc/convert-host.ts b/src/misc/convert-host.ts
index ae4f20dc4b67..3ad024186518 100644
--- a/src/misc/convert-host.ts
+++ b/src/misc/convert-host.ts
@@ -1,5 +1,5 @@
 import config from '../config';
-import { toUnicode, toASCII } from 'punycode';
+import { toUnicode, toASCII } from 'punycode/';
 import { URL } from 'url';
 
 export function getFullApAccount(username: string, host: string | null) {
diff --git a/src/misc/pack-emojis.ts b/src/misc/pack-emojis.ts
index 479f7f646149..911ef03743d8 100644
--- a/src/misc/pack-emojis.ts
+++ b/src/misc/pack-emojis.ts
@@ -1,6 +1,6 @@
 import User from '../models/user';
 import Emoji from '../models/emoji';
-import { toUnicode, toASCII } from 'punycode';
+import { toUnicode, toASCII } from 'punycode/';
 import config from '../config';
 import { isSelfHost } from './convert-host';
 import getDriveFileUrl from './get-drive-file-url';
diff --git a/src/queue/processors/inbox.ts b/src/queue/processors/inbox.ts
index 6722a8471f44..646eb6090095 100644
--- a/src/queue/processors/inbox.ts
+++ b/src/queue/processors/inbox.ts
@@ -3,7 +3,7 @@ import * as httpSignature from 'http-signature';
 import { IRemoteUser } from '../../models/user';
 import perform from '../../remote/activitypub/perform';
 import { resolvePerson } from '../../remote/activitypub/models/person';
-import { toUnicode } from 'punycode';
+import { toUnicode } from 'punycode/';
 import { URL } from 'url';
 import Logger from '../../services/logger';
 import { registerOrFetchInstanceDoc } from '../../services/register-or-fetch-instance-doc';
diff --git a/src/remote/activitypub/models/note.ts b/src/remote/activitypub/models/note.ts
index 26632b1fd775..df6055669cca 100644
--- a/src/remote/activitypub/models/note.ts
+++ b/src/remote/activitypub/models/note.ts
@@ -12,7 +12,7 @@ import { htmlToMfm } from '../misc/html-to-mfm';
 import Emoji, { IEmoji } from '../../../models/emoji';
 import { extractApMentions } from './mention';
 import { extractApHashtags } from './tag';
-import { toUnicode } from 'punycode';
+import { toUnicode } from 'punycode/';
 import { unique, toArray, toSingle } from '../../../prelude/array';
 import { extractPollFromQuestion } from './question';
 import vote from '../../../services/note/polls/vote';
diff --git a/src/remote/activitypub/models/person.ts b/src/remote/activitypub/models/person.ts
index 0f288e8111c3..714c01da2314 100644
--- a/src/remote/activitypub/models/person.ts
+++ b/src/remote/activitypub/models/person.ts
@@ -1,6 +1,6 @@
 import * as mongo from 'mongodb';
 import * as promiseLimit from 'promise-limit';
-import { toUnicode } from 'punycode';
+import { toUnicode } from 'punycode/';
 
 import config from '../../../config';
 import User, { validateUsername, IUser, IRemoteUser, isRemoteUser } from '../../../models/user';
diff --git a/src/remote/resolve-user.ts b/src/remote/resolve-user.ts
index bffcd581cca3..707b2012554b 100644
--- a/src/remote/resolve-user.ts
+++ b/src/remote/resolve-user.ts
@@ -1,4 +1,4 @@
-import { toUnicode, toASCII } from 'punycode';
+import { toUnicode, toASCII } from 'punycode/';
 import User, { IUser, IRemoteUser } from '../models/user';
 import webFinger from './webfinger';
 import config from '../config';
diff --git a/src/server/api/common/get-host-lower.ts b/src/server/api/common/get-host-lower.ts
index 26ddf6c6d080..4293b3951f4c 100644
--- a/src/server/api/common/get-host-lower.ts
+++ b/src/server/api/common/get-host-lower.ts
@@ -1,4 +1,4 @@
-import { toUnicode } from 'punycode';
+import { toUnicode } from 'punycode/';
 
 export default (host: string) => {
 	if (host == null) return null;
diff --git a/src/services/note/create.ts b/src/services/note/create.ts
index 8b3c4b0388e6..3bf7398c8ea8 100644
--- a/src/services/note/create.ts
+++ b/src/services/note/create.ts
@@ -27,7 +27,7 @@ import { erase, concat, unique } from '../../prelude/array';
 import insertNoteUnread from './unread';
 import { registerOrFetchInstanceDoc } from '../register-or-fetch-instance-doc';
 import Instance from '../../models/instance';
-import { toASCII } from 'punycode';
+import { toASCII } from 'punycode/';
 import extractMentions from '../../misc/extract-mentions';
 import extractEmojis from '../../misc/extract-emojis';
 import extractHashtags from '../../misc/extract-hashtags';
diff --git a/yarn.lock b/yarn.lock
index 0bf739abb73f..bb53b8b0bf7c 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -631,6 +631,11 @@
   resolved "https://registry.yarnpkg.com/@types/pug/-/pug-2.0.4.tgz#8772fcd0418e3cd2cc171555d73007415051f4b2"
   integrity sha1-h3L80EGOPNLMFxVV1zAHQVBR9LI=
 
+"@types/punycode@2.1.0":
+  version "2.1.0"
+  resolved "https://registry.yarnpkg.com/@types/punycode/-/punycode-2.1.0.tgz#89e4f3d09b3f92e87a80505af19be7e0c31d4e83"
+  integrity sha512-PG5aLpW6PJOeV2fHRslP4IOMWn+G+Uq8CfnyJ+PDS8ndCbU+soO+fB3NKCKo0p/Jh2Y4aPaiQZsrOXFdzpcA6g==
+
 "@types/q@^1.5.1":
   version "1.5.2"
   resolved "https://registry.yarnpkg.com/@types/q/-/q-1.5.2.tgz#690a1475b84f2a884fd07cd797c00f5f31356ea8"