Last name Tongseng (Tongseng 
) , all over the world, is a rare family name. The surname Tongseng is characteristic of South-eastern Asia, particularly Thailand, where it is a very rare surname, Indonesia, and Malaysia, where it is an extremely rare surname. In absolute terms, this name is the most popular in Indonesia, Thailand, and China. Much less frequently, Tongseng is the forename as well as the last name.