diff --git a/science/py-ase/Makefile b/science/py-ase/Makefile
index 75ff517ccdb6..a6af49aa8a03 100644
--- a/science/py-ase/Makefile
+++ b/science/py-ase/Makefile
@@ -19,7 +19,7 @@ RUN_DEPENDS=	${PYTHON_PKGNAMEPREFIX}Flask>0:www/py-flask@${PY_FLAVOR} \
 		${PYNUMPY} \
 		nwchem:science/nwchem
 
-USES=		python
+USES=		python:3.5+
 USE_PYTHON=	distutils concurrent autoplist
 
 NO_ARCH=	yes