diff --git a/bson/bson.go b/bson/bson.go
index 579aec13f..e2804b9bf 100644
--- a/bson/bson.go
+++ b/bson/bson.go
@@ -558,6 +558,9 @@ func Unmarshal(in []byte, out interface{}) (err error) {
 // See the Unmarshal function documentation for more details on the
 // unmarshalling process.
 func (raw Raw) Unmarshal(out interface{}) (err error) {
+	if len(raw.Data) == 0 {
+		return SetZero
+	}
 	defer handleErr(&err)
 	v := reflect.ValueOf(out)
 	switch v.Kind() {