diff --git a/www/py-werkzeug/Makefile b/www/py-werkzeug/Makefile
index 8d4c304698d0..aa5d05ede3a0 100644
--- a/www/py-werkzeug/Makefile
+++ b/www/py-werkzeug/Makefile
@@ -28,6 +28,7 @@ WATCHDOG_RUN_DEPENDS=	${PYTHON_PKGNAMEPREFIX}watchdog>=0:devel/py-watchdog@${PY_
 .include <bsd.port.pre.mk>
 
 .if ${PYTHON_REL} < 3700
+BUILD_DEPENDS+=	${PYTHON_PKGNAMEPREFIX}dataclasses>=0:devel/py-dataclasses@${PY_FLAVOR}
 RUN_DEPENDS+=	${PYTHON_PKGNAMEPREFIX}dataclasses>=0:devel/py-dataclasses@${PY_FLAVOR}
 .endif