Do I need photo and if so, what is its size?

Yes, you do. However, photos are required upon arrival at an airport in Vietnam, so please remember to bring at least 2 photos of standard passport size (04*06 cm or similar - No need to be exact size).

Note: If you do not have time to prepare those photos before your departure, you can also get them taken at a Vietnamese airport for 2 USD or less per photo. But this is not advised unless it is an urgent case.