diff --git a/setup.py b/setup.py
index 853aad57ac78..b050394d239f 100644
--- a/setup.py
+++ b/setup.py
@@ -51,6 +51,10 @@ def find_data_files(base, globs):
 
     return rv
 
+install_requires = [
+    'lxml==3.4.4'
+]
+
 data_files = []
 
 data_files += find_data_files('typeshed', ['*.py', '*.pyi'])
@@ -80,6 +84,7 @@ def find_data_files(base, globs):
       platforms=['POSIX'],
       package_dir={'': 'lib-typing/3.2', 'mypy': 'mypy'},
       py_modules=['typing'],
+      install_requires=install_requires,
       packages=['mypy'],
       scripts=['scripts/mypy'],
       data_files=data_files,
diff --git a/test-requirements.txt b/test-requirements.txt
index 6d831fb1196b..bb9560449100 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -1 +1,2 @@
 flake8==2.4.1
+lxml==3.4.4