diff --git a/xsd-types/src/types/duration.rs b/xsd-types/src/types/duration.rs
index ccaffbe..d8f5f56 100644
--- a/xsd-types/src/types/duration.rs
+++ b/xsd-types/src/types/duration.rs
@@ -301,6 +301,8 @@ mod tests {
 
     #[test]
     fn duration_parsing_test() {
+        assert_eq!(Duration::from_str(""), Duration::from_str("PT0S"));
+        check_valid("PT0S");
         check_valid("P2Y6M5DT12H35M30S");
         check_valid("P1DT2H");
         check_valid("P20M");