| Magika Pallacanestro | — | Castel San Pietro Terme | — | — |
| Magnolia Basket Campobasso | — | काम्पोबास्सो | 2017 | — |
| Mariscal Miller | Copa Perú | — | — | Estadio Jorge Basadre |
| Mariscal Nieto de Ilo | Copa Perú | — | — | Estadio Mariscal Nieto |
| Mariscal Sucre | — | — | 1925 | National Stadium of Peru |
| Maurolico Messina | — | — | — | — |
| Maxima Roma | Serie A | — | 2026 | Palazzo dello Sport |
| Mens Sana Basket | Serie A | सियेना | 1861 | Palasport Mens Sana |
| Merchants United Social, Sports and Cultural Association | Peruvian Primera División | — | 19 सितंबर 2002 | Juan Maldonado Gamarra Stadium |
| Meyana Mesagne | — | Mesagne | — | — |
| Miguel Grau de Abancay | Copa Perú | — | 1955 | Estadio Monumental de Condebamba |
| Milwaukee Braves | मेजर लीग बेसबॉल | मिल्वौकी | 1953 | Milwaukee County Stadium |
| Mina San Vicente | Copa Perú | — | जून 1970 | — |
| Minnesota North Stars | नैशनल हॉकी लीग | Bloomington | 1967 | Met Center |
| Minnesota United FC | मेजर लीग सॉकर | मिनियापोलिस | 2015 | Allianz Field, Huntington Bank Stadium |
| Miraflores Sporting Club | — | — | — | Estadio Nacional del Perú (1897) |
| Montigarda Basket | — | Montichiari | — | — |
| Montreal Expos | मेजर लीग बेसबॉल | — | 1969 | Olympic Stadium, Jarry Park Stadium |
| Montreal Maroons | — | — | 1924 | Montreal Forum |
| MTVB Herons Basket | — | Montecatini Terme | — | — |