Last name Oini (Oini 
) , all over the world, is a very rare family name. The surname Oini is habitual in Malaysia, where it is a very rare surname, Venezuela, where it is an extremely rare surname, and China. Not in comparison with a country's population, it most frequently occurs in China, Malaysia, and India. More frequently, Oini is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Oini | Japan, China, Malaysia, Papua New Guinea, India |