diff --git a/configstruct.go b/configstruct.go
index 3509d36..043c4c0 100644
--- a/configstruct.go
+++ b/configstruct.go
@@ -55,7 +55,7 @@ func ParseWithFlagSet(flagSet *flag.FlagSet, cliArgs []string, c interface{}, op
 					return fmt.Errorf("argument %s is required", name)
 				}
 
-				if required {
+				if argVal != "" {
 					value.Set(reflect.ValueOf(argVal))
 				}
 			}