Cognomen ประจงค์ (ประจงค์ 
) , in the entire world, is a very rare last name. The last name ประจงค์ is habitual in South-eastern Asia, particularly Thailand, where it is a very rare surname. Much less frequently, ประจงค์ is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| ประจงค์ | Thailand |