diff --git a/package.json b/package.json
index 57ea27f..b3e26f5 100644
--- a/package.json
+++ b/package.json
@@ -9,20 +9,18 @@
   "bugs": {
     "url": "https://github.com/kazupon/vue-i18n-locale-message/issues"
   },
-  "types": "types/index.d.ts",
-  "files": [
-    "types",
-    "lib",
-    "src"
-  ],
   "dependencies": {
     "@vue/component-compiler-utils": "^3.0.0",
     "debug": "^4.1.1",
+    "js-yaml": "^3.13.1",
+    "json5": "^2.1.0",
     "vue-template-compiler": "^2.6.10"
   },
   "devDependencies": {
     "@types/debug": "^4.1.4",
     "@types/jest": "^24.0.15",
+    "@types/js-yaml": "^3.12.1",
+    "@types/json5": "^0.0.30",
     "@types/node": "^12.6.8",
     "@typescript-eslint/eslint-plugin": "^1.13.0",
     "@typescript-eslint/parser": "^1.13.0",
@@ -43,6 +41,11 @@
   "engines": {
     "node": ">= 8"
   },
+  "files": [
+    "types",
+    "lib",
+    "src"
+  ],
   "homepage": "https://github.com/kazupon/vue-i18n-locale-message#readme",
   "keywords": [
     "i18n",
@@ -59,14 +62,15 @@
   },
   "scripts": {
     "build": "tsc -p .",
-    "test:cover": "npm run test:unit -- --coverage",
-    "test:unit": "jest --env node",
-    "watch": "tsc -p . --watch",
+    "changelog": "conventional-changelog -i CHANGELOG.md -s -n ./node_modules/git-commit-message-convention/convention.js",
+    "clean": "rm -rf ./coverage && rm -rf ./lib/*.js*",
+    "coverage": "opener coverage/lcov-report/index.html",
     "lint": "eslint ./src ./test --ext .ts",
     "release": "conventional-github-releaser -n ./node_modules/git-commit-message-convention/convention.js",
     "test": "npm run lint && npm run test:cover",
-    "changelog": "conventional-changelog -i CHANGELOG.md -s -n ./node_modules/git-commit-message-convention/convention.js",
-    "clean": "rm -rf ./coverage && rm -rf ./lib/*.js*",
-    "coverage": "opener coverage/lcov-report/index.html"
-  }
+    "test:cover": "npm run test:unit -- --coverage",
+    "test:unit": "jest --env node",
+    "watch": "tsc -p . --watch"
+  },
+  "types": "types/index.d.ts"
 }
diff --git a/src/squeezer.ts b/src/squeezer.ts
index 8820d40..2e059c0 100644
--- a/src/squeezer.ts
+++ b/src/squeezer.ts
@@ -3,6 +3,8 @@ import { VueTemplateCompiler } from '@vue/component-compiler-utils/dist/types'
 
 import { parse } from '@vue/component-compiler-utils'
 import * as compiler from 'vue-template-compiler'
+import JSON5 from 'json5'
+import yaml from 'js-yaml'
 
 import { debug as Debug } from 'debug'
 const debug = Debug('vue-i18n-locale-messages:squeezer')
@@ -37,8 +39,10 @@ function squeezeFromI18nBlock (content: string): LocaleMessages {
   })
 
   return desc.customBlocks.reduce((messages, block) => {
+    debug('i18n block attrs', block.attrs)
     if (block.type === 'i18n') {
-      const obj = JSON.parse(block.content)
+      const lang = block.attrs.lang as string || 'json'
+      const obj = parseContent(block.content, lang)
       if (block.attrs.locale) {
         return Object.assign(messages, { [block.attrs.locale as string]: obj })
       } else {
@@ -49,3 +53,16 @@ function squeezeFromI18nBlock (content: string): LocaleMessages {
     }
   }, {})
 }
+
+function parseContent (content: string, lang: string): any {
+  switch (lang) {
+    case 'yaml':
+    case 'yml':
+      return yaml.safeLoad(content)
+    case 'json5':
+      return JSON5.parse(content)
+    case 'json':
+    default:
+      return JSON.parse(content)
+  }
+}
diff --git a/test/__snapshots__/squeezer.test.ts.snap b/test/__snapshots__/squeezer.test.ts.snap
index 217ecd9..95b4954 100644
--- a/test/__snapshots__/squeezer.test.ts.snap
+++ b/test/__snapshots__/squeezer.test.ts.snap
@@ -1,6 +1,6 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
-exports[`squeeze 1`] = `
+exports[`basic 1`] = `
 Object {
   "en": Object {
     "App": Object {
@@ -45,3 +45,45 @@ Object {
   },
 }
 `;
+
+exports[`json5 1`] = `
+Object {
+  "en": Object {
+    "Modal": Object {
+      "components": Object {
+        "cancel": "Cancel",
+        "ok": "OK",
+      },
+    },
+  },
+  "ja": Object {
+    "Modal": Object {
+      "components": Object {
+        "cancel": "キャンセル",
+        "ok": "OK",
+      },
+    },
+  },
+}
+`;
+
+exports[`yaml 1`] = `
+Object {
+  "en": Object {
+    "Modal": Object {
+      "components": Object {
+        "cancel": "Cancel",
+        "ok": "OK",
+      },
+    },
+  },
+  "ja": Object {
+    "Modal": Object {
+      "components": Object {
+        "cancel": "キャンセル",
+        "ok": "OK",
+      },
+    },
+  },
+}
+`;
diff --git a/test/fixtures/format/json5.ts b/test/fixtures/format/json5.ts
new file mode 100644
index 0000000..2be4143
--- /dev/null
+++ b/test/fixtures/format/json5.ts
@@ -0,0 +1,20 @@
+export default [{
+  contentPath: '/path/to/project1/src/components/Modal.vue',
+  content: `
+  <i18n locale="en" lang="json5">
+  {
+     // modal contents
+     "ok": "OK",
+     cancel: "Cancel"
+  }
+  </i18n>
+  <i18n locale="ja">
+  {
+     "ok": "OK",
+     "cancel": "キャンセル"
+  }
+  </i18n>
+  `,
+  component: 'Modal',
+  messageHierarchy: ['components', 'Modal']
+}]
diff --git a/test/fixtures/format/yaml.ts b/test/fixtures/format/yaml.ts
new file mode 100644
index 0000000..9e16eb9
--- /dev/null
+++ b/test/fixtures/format/yaml.ts
@@ -0,0 +1,15 @@
+export default [{
+  contentPath: '/path/to/project1/src/components/Modal.vue',
+  content: `
+  <i18n locale="en" lang="yaml">
+    ok: "OK"
+    cancel: "Cancel"
+  </i18n>
+  <i18n locale="ja" lang="yml">
+    ok: OK
+    cancel: キャンセル
+  </i18n>
+  `,
+  component: 'Modal',
+  messageHierarchy: ['components', 'Modal']
+}]
diff --git a/test/squeezer.test.ts b/test/squeezer.test.ts
index 9f02fe2..c43fd5a 100644
--- a/test/squeezer.test.ts
+++ b/test/squeezer.test.ts
@@ -1,8 +1,20 @@
 import squeeze from '../src/squeezer'
 import metaInfo from './fixtures/meta'
+import yamlMetaInfo from './fixtures/format/yaml'
+import json5MetaInfo from './fixtures/format/json5'
 import { LocaleMessages, LocaleMessageMeta } from '../types'
 
-test('squeeze', () => {
+test('basic', () => {
   const mesasges: LocaleMessages = squeeze(metaInfo as LocaleMessageMeta[])
   expect(mesasges).toMatchSnapshot()
 })
+
+test('yaml', () => {
+  const mesasges: LocaleMessages = squeeze(yamlMetaInfo as LocaleMessageMeta[])
+  expect(mesasges).toMatchSnapshot()
+})
+
+test('json5', () => {
+  const mesasges: LocaleMessages = squeeze(json5MetaInfo as LocaleMessageMeta[])
+  expect(mesasges).toMatchSnapshot()
+})
diff --git a/yarn.lock b/yarn.lock
index 808b1b6..07c8d30 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -365,11 +365,21 @@
   dependencies:
     "@types/jest-diff" "*"
 
+"@types/js-yaml@^3.12.1":
+  version "3.12.1"
+  resolved "https://registry.yarnpkg.com/@types/js-yaml/-/js-yaml-3.12.1.tgz#5c6f4a1eabca84792fbd916f0cb40847f123c656"
+  integrity sha512-SGGAhXLHDx+PK4YLNcNGa6goPf9XRWQNAUUbffkwVGGXIxmDKWyGGL4inzq2sPmExu431Ekb9aEMn9BkPqEYFA==
+
 "@types/json-schema@^7.0.3":
   version "7.0.3"
   resolved "https://registry.yarnpkg.com/@types/json-schema/-/json-schema-7.0.3.tgz#bdfd69d61e464dcc81b25159c270d75a73c1a636"
   integrity sha512-Il2DtDVRGDcqjDtE+rF8iqg1CArehSK84HZJCT7AMITlyXRBpuPhqGLDQMowraqqu1coEaimg4ZOqggt6L6L+A==
 
+"@types/json5@^0.0.30":
+  version "0.0.30"
+  resolved "https://registry.yarnpkg.com/@types/json5/-/json5-0.0.30.tgz#44cb52f32a809734ca562e685c6473b5754a7818"
+  integrity sha512-sqm9g7mHlPY/43fcSNrCYfOeX9zkTTK+euO5E6+CVijSMm5tTjkVdwdqRkY3ljjIAf8679vps5jKUoJBCLsMDA==
+
 "@types/node@^12.6.8":
   version "12.6.8"
   resolved "https://registry.yarnpkg.com/@types/node/-/node-12.6.8.tgz#e469b4bf9d1c9832aee4907ba8a051494357c12c"