Family name Osvaldo Guillermo (Osvaldo Guillermo 
) , globally, is a very rare last name. The cognomen Osvaldo Guillermo is habitual in Latin America and the Caribbean, particularly Chile, where it is a rare surname. More prevalently, Osvaldo Guillermo is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Osvaldo Guillermo | Argentina, Chile, Spain, Costa Rica |