Family name Somboonjai (Somboonjai 
) , all around the world, is a rare last name. The family name Somboonjai is habitual in South-eastern Asia, particularly Thailand, where it is a rare surname. Very seldom, Somboonjai is the forename as well as the last name.
Paiwan, Sarawut, Tansiri, Walaporn, Sasipong, Permpoon, Rungtiwa, Nattakan, Nithchakoon, Boonchaey, Walaiporn, Sarunyapong, and Ratchadawan