diff --git a/binding.gyp b/binding.gyp
index c2f9c6526d2b138fd57673a664f817d982da79b7..52e0ea6c394e89478927ed37465d8568f2acc4ba 100644
--- a/binding.gyp
+++ b/binding.gyp
@@ -55,7 +55,8 @@
     'include_dirs': [
       '.',
       'include',
-      '<(node_root_dir)/deps/openssl/openssl/include'
+      '<(node_root_dir)/deps/openssl/openssl/include',
+      '<(node_root_dir)/deps/zlib'
     ],
     'conditions': [
       ['OS != "win"', {