diff --git a/builder/googlecompute/config.go b/builder/googlecompute/config.go
index b09f1814e..8ed3897d6 100644
--- a/builder/googlecompute/config.go
+++ b/builder/googlecompute/config.go
@@ -82,7 +82,7 @@ func NewConfig(raws ...interface{}) (*Config, []string, error) {
 	var errs *packer.MultiError
 
 	// Set defaults.
-	if c.Network == "" {
+	if c.Network == "" && c.Subnetwork == "" {
 		c.Network = "default"
 	}