Family name Romilio Guillermo (Romilio Guillermo 
) , all around the world, is an extremely rare surname. The cognomen Romilio Guillermo is characteristic of Latin America and the Caribbean, particularly Chile, where it is an extremely rare surname. More frequently, Romilio Guillermo is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Romilio Guillermo | Chile |