Family name Koio (Koio 
) , all around the world, is a very rare surname. The surname Koio is characteristic of Indonesia, where it is a very rare surname, Nigeria, where it is an extremely rare surname, and Brazil. Measured by absolute frequency, it is the most numerous in Indonesia, China, and Nigeria. Much less frequently, Koio is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Koio | Nigeria, Brazil, Indonesia, Malaysia, China |