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