diff --git a/lib/context.js b/lib/context.js
index 019fe8891c..95065b540d 100644
--- a/lib/context.js
+++ b/lib/context.js
@@ -1,11 +1,5 @@
 'use strict';
 
-/**
- * Module dependencies.
- */
-
-var JSON = require('json3');
-
 /**
  * Expose `Context`.
  */
diff --git a/lib/reporters/json-stream.js b/lib/reporters/json-stream.js
index 6126e47ea1..c0d79cf970 100644
--- a/lib/reporters/json-stream.js
+++ b/lib/reporters/json-stream.js
@@ -5,7 +5,6 @@
  */
 
 var Base = require('./base');
-var JSON = require('json3');
 
 /**
  * Expose `List`.
diff --git a/lib/runnable.js b/lib/runnable.js
index 03d41f9d51..946f278341 100644
--- a/lib/runnable.js
+++ b/lib/runnable.js
@@ -5,7 +5,6 @@
  */
 
 var EventEmitter = require('events').EventEmitter;
-var JSON = require('json3');
 var Pending = require('./pending');
 var debug = require('debug')('mocha:runnable');
 var milliseconds = require('./ms');
diff --git a/lib/utils.js b/lib/utils.js
index 9bac5a8cf7..a4357258cf 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -6,7 +6,6 @@
  * Module dependencies.
  */
 
-var JSON = require('json3');
 var basename = require('path').basename;
 var debug = require('debug')('mocha:watch');
 var exists = require('fs').existsSync || require('path').existsSync;
diff --git a/package.json b/package.json
index 56f75f7546..5f5b24c9ed 100644
--- a/package.json
+++ b/package.json
@@ -313,7 +313,6 @@
     "glob": "7.1.2",
     "growl": "1.10.2",
     "he": "1.1.1",
-    "json3": "3.3.2",
     "mkdirp": "0.5.1",
     "supports-color": "4.4.0"
   },
diff --git a/test/unit/utils.spec.js b/test/unit/utils.spec.js
index cb33a7c520..b945784438 100644
--- a/test/unit/utils.spec.js
+++ b/test/unit/utils.spec.js
@@ -2,7 +2,6 @@
 
 var utils = require('../../lib/utils');
 var toISOString = require('../../lib/to-iso-string');
-var JSON = require('json3');
 
 describe('lib/utils', function () {
   describe('clean', function () {