diff --git a/yaml.go b/yaml.go
index 089a82c..3b386d7 100755
--- a/yaml.go
+++ b/yaml.go
@@ -85,7 +85,7 @@ func (y *Yaml) GetStream(key string, ns ...string) (io.Reader, error) {
 	if !ok {
 		return nil, ErrNotFound
 	}
-	if strings.HasPrefix("b64://", s) {
+	if strings.HasPrefix(s, "b64://") {
 		b, err := base64.StdEncoding.DecodeString(strings.TrimPrefix(s, "b64://"))
 		return bytes.NewReader(b), err
 	}