Cognomen Guerreyro (Guerreyro 
) , all around the world, is a very rare last name. The last name Guerreyro is habitual in Latin America and the Caribbean, particularly Peru, where it is a rare surname. Much less frequently, Guerreyro is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Guerreyro | Peru |