Surname Muai (หมวย 
, Muai 
, หม่วย) , in the world, is a rare family name. The surname Muai is characteristic of Angola, where it is a rare surname, Malaysia, and Thailand, where it is a very rare surname. In absolute terms, it is commonest in Angola, Malaysia, and Indonesia. More prevalently, Muai is the forename as well as the last name.