Cognomen Thongkhoon (Thongkhoon 
) , across the world, is an extremely rare family name. The family name Thongkhoon is characteristic of South-eastern Asia, particularly Thailand, where it is an extremely rare surname. More prevalently, Thongkhoon is the forename as well as the last name.
Upree, Namsai, Nuhaisap, Buangoen, and Rattanaphouly