Cognomen ธรรมบุญ (Dharma 
, ธรรมบุญ 
, Thambun 
) , around the world, is a common surname. The family name ธรรมบุญ is characteristic of Indonesia, where it is quite a common surname, Qatar, where it is quite a rare surname, and United Arab Emirates. In absolute terms, it is the most numerous in Indonesia, India, and Nepal. More prevalently, ธรรมบุญ is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Dharma | Saudi Arabia, Nepal, India, Sri Lanka, Indonesia |
| Thanmaboon, ธรรมบุญ | Thailand |
| Thambun | Thailand, United States |
Thamdomboon, and Thasombun