Family name Ryeo (Ryeo 
, เรียว 
) , all around the world, is a rare surname. The cognomen Ryeo is characteristic of South Korea, where it is a rare surname, Vietnam, where it is a very rare surname, and Thailand, where it is an extremely rare surname. Not in comparison with a country's population, it is commonest in South Korea, Vietnam, and China. Also, Ryeo is the forename as well as the last name.