Cognomen Oreyano (Oreyano 
) , across the world, is a very rare last name. The cognomen Oreyano is habitual in Latin America and the Caribbean, particularly Nicaragua, where it is a rare surname, Argentina, where it is a very rare surname, and Venezuela, where it is an extremely rare surname. Much less frequently, Oreyano is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Oreyano | Venezuela, Argentina, Nicaragua, Peru |