diff --git a/third_party/zip/android.go b/third_party/zip/android.go
index f8e45c5..0f41f62 100644
--- a/third_party/zip/android.go
+++ b/third_party/zip/android.go
@@ -170,7 +170,7 @@
 func (w *Writer) CreateHeaderAndroid(fh *FileHeader) (io.Writer, error) {
 	writeDataDescriptor := fh.Method != Store
 	if writeDataDescriptor {
-		fh.Flags &= DataDescriptorFlag
+		fh.Flags |= DataDescriptorFlag
 	} else {
 		fh.Flags &= ^uint16(DataDescriptorFlag)
 	}