Family name คุณประสิทธิ์ (Prasit 
, คุณประสิทธิ์ ) , throughout the world, is quite a rare last name. The cognomen คุณประสิทธิ์ is habitual in South-eastern Asia, particularly Thailand, where it is quite a rare surname, Malaysia, where it is a rare surname, and Singapore, where it is a very rare surname. Measured by absolute frequency, it most frequently occurs in Thailand, Malaysia, and China. Predominantly, คุณประสิทธิ์ is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Prasit | Thailand, Nepal, United States, India, Indonesia |
| คุณประสิทธิ์ | Thailand |