Throughout the world, Marco Arnaldo (Marco Arnaldo 
) is a very rare male forename. The first name Marco Arnaldo is habitual in Latin America and the Caribbean, particularly Chile, where it is a very rare boy's name, and Peru. Much less frequently, Marco Arnaldo is the last name as well as the forename.
| VARIANT | COUNTRY |
|---|---|
| Marco Arnaldo | Peru, Ecuador, Chile, Costa Rica |