Surname Ongchan (Ongchan 
) , around the globe, is a very rare cognomen. The last name Ongchan is habitual in Philippines, where it is a very rare surname, Thailand, where it is an extremely rare surname, and China. Much less frequently, Ongchan is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Ongchan | China, Philippines, Thailand |