| Miguela | | - | Spanish, Portuguese | |
| Miguelangel | | mee-gel-AHN-khel | Spanish | |
| Miguelito | | - | Spanish, Portuguese | |
| Milagros | | mee-LAH-gros | Spanish | |
| Mireia | | mee-RE-yə (Catalan) | Catalan, Spanish | |
| Mireya | | - | Spanish | |
| Mirta | | - | Spanish, Italian, Croatian | |
| Modesta | | mo-DHE-stah (Spanish) | Spanish, Late Roman | |
| Modesto | | mo-DHE-sto (Spanish, Italian) | Spanish, Italian, Portuguese | |
| MoisÉS | | moi-SES (Spanish) | Spanish, Portuguese | |
| NÉLida | | - | Literature, Spanish | |
| Nacho | | NAH-cho | Spanish | |
| Nacio | | NAH-thyo (Spanish), NAH-syo (Latin American Spanish) | Spanish | |
| Nando | | - | Spanish | |
| Narcisa | | - | Portuguese, Spanish, Italian, Romanian | |