Family name สมพันธ์ (สมพันธ์ 
, Somphan 
, Somphun ) , worldwide, is quite a rare last name. The cognomen สมพันธ์ is characteristic of South-eastern Asia, particularly Thailand, where it is quite a rare surname. Likewise, สมพันธ์ is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Soompan, สมพันธ์ | Thailand |
| Somphan | Norway, Laos, United States, Thailand, New Zealand |
| Somphun | United States, Thailand |
Samomphan, Somfhun, Sommaphun, Sompaan, Sompahn, Sompanpa, Sompanpare, Sompanpene, Sompanphae, Sompanphang, Sompanphiang, Somphandh, Somphanjan, Somphanphiag, Somphunh, Sompunpare, and Sormphan