diff --git a/compose/config/config.py b/compose/config/config.py
index 2faa12b2d..102758e9d 100644
--- a/compose/config/config.py
+++ b/compose/config/config.py
@@ -87,6 +87,7 @@ ALLOWED_KEYS = DOCKER_CONFIG_KEYS + [
     'container_name',
     'dockerfile',
     'logging',
+    'network_mode',
 ]
 
 DOCKER_VALID_URL_PREFIXES = (