Family name Toyomasu (Toyomasu 
) , in the world, is a very rare last name. The cognomen Toyomasu is habitual in Norway, where it is a rare surname, and Brazil, where it is an extremely rare surname. Also, Toyomasu is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Toyomasu | Japan, Norway, Brazil |