diff --git a/setup.py b/setup.py
index <HASH>..<HASH> 100644
--- a/setup.py
+++ b/setup.py
@@ -65,6 +65,7 @@ An extensive
         'Programming Language :: Python :: 3.3',
         'Programming Language :: Python :: 3.4',
         'Programming Language :: Python :: 3.5',
+        'Programming Language :: Python :: Implementation :: PyPy',
         'Topic :: Software Development :: Libraries :: Python Modules',
     ],
 )
Added "Implementation :: PyPy" to classifiers.