Surname ธัญพืช (Grasin 
, Graisen , ธัญพืช ) , in all the world, is a rare family name. The family name ธัญพืช is habitual in Romania, where it is a rare surname, Thailand, where it is a very rare surname, and Germany, where it is an extremely rare surname. Likewise, ธัญพืช is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Grasin | Romania, Germany, Thailand, United States, India |
| Graisen | Thailand, United States |
| Grainugool, ธัญพืช | Thailand |
Graisin, and Thanyaphuet