Family name อุบลเพ็ญ (อุบลเพ็ญ 
, Ubonpen , Ubonphen ) , all around the world, is a very rare surname. The cognomen อุบลเพ็ญ is characteristic of South-eastern Asia, particularly Thailand, where it is a very rare surname. Very seldom, อุบลเพ็ญ is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| อุบลเพ็ญ, Ubonpen, Ubonphen | Thailand |