diff --git a/lib/theme/processors/source.js b/lib/theme/processors/source.js
index 9bdf509449..a306686f8f 100644
--- a/lib/theme/processors/source.js
+++ b/lib/theme/processors/source.js
@@ -3,6 +3,10 @@
 var Pattern = require('hexo-util').Pattern;
 var common = require('../../plugins/processor/common');
 
+function startsWith(str, prefix){
+  return str.substring(0, prefix.length) === prefix;
+}
+
 exports.process = function(file) {
   var Asset = this.model('Asset');
   var id = file.source.substring(this.base_dir.length).replace(/\\/g, '/');
@@ -27,10 +31,10 @@ exports.process = function(file) {
 };
 
 exports.pattern = new Pattern(function(path) {
-  if (path.substring(0, 7) !== 'source/') return false;
+  if (!startsWith(path, 'source/')) return false;
 
   path = path.substring(7);
-  if (common.isHiddenFile(path) || common.isTmpFile(path)) return false;
+  if (common.isHiddenFile(path) || common.isTmpFile(path) || ~path.indexOf('node_modules')) return false;
 
   return {path: path};
 });
diff --git a/test/scripts/theme_processors/source.js b/test/scripts/theme_processors/source.js
index 05d4af45ce..5924a61733 100644
--- a/test/scripts/theme_processors/source.js
+++ b/test/scripts/theme_processors/source.js
@@ -46,6 +46,8 @@ describe('source', function() {
     pattern.match('source/foo.jpg%').should.be.false;
     pattern.match('layout/foo.swig').should.be.false;
     pattern.match('package.json').should.be.false;
+    pattern.match('node_modules/test/test.js').should.be.false;
+    pattern.match('source/node_modules/test/test.js').should.be.false;
   });
 
   it('type: create', function() {