Family name Koyamu (Koyamu 
) , all around the world, is a very rare surname. The family name Koyamu is habitual in Malaysia, where it is a very rare surname, and India, where it is an extremely rare surname. Much more frequently, Koyamu is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Koyamu | India, Malaysia |