| Name | What | Region | Country | Lat | Long | Elev ft. | Pop est |
|---|---|---|---|---|---|---|---|
| Machungo | city | Departamento de San Martin | Peru | -6.68 | -76.27 | 1135 | 3778 |
| Malvinas | city | Departamento de San Martin | Peru | -5.91 | -77.01 | 2677 | 3291 |
| Maman | city | Departamento de San Martin | Peru | -8.44 | -76.85 | 5396 | 149 |
| Mamonaquihua | city | Departamento de San Martin | Peru | -6.65 | -76.43 | 987 | 2083 |
| Manantial | city | Departamento de San Martin | Peru | -5.86 | -77.11 | 2490 | 2235 |
| Manco Capac | city | Departamento de San Martin | Peru | -8.21 | -76.47 | 1673 | 4408 |
| Manizales | city | Departamento de San Martin | Peru | -6.17 | -77.07 | 3454 | 6187 |
| Manquinte | city | Departamento de San Martin | Peru | -8.55 | -76.49 | 2444 | 2836 |
| Mantencion | city | Departamento de San Martin | Peru | -8.23 | -76.43 | 1719 | 4386 |
| Mariscal Castilla | city | Departamento de San Martin | Peru | -6.72 | -76.40 | 971 | 1304 |
| Marona | city | Departamento de San Martin | Peru | -8.71 | -76.11 | 2526 | 1250 |
| Maronilla | city | Departamento de San Martin | Peru | -8.70 | -76.14 | 2181 | 1427 |
| Mashuyacu | city | Departamento de San Martin | Peru | -6.11 | -77.19 | 2818 | 12513 |
| Mechungo | city | Departamento de San Martin | Peru | -6.68 | -76.27 | 1135 | 3778 |
| Mego | city | Departamento de San Martin | Peru | -6.62 | -76.33 | 820 | 3934 |
| Miguel Grau | city | Departamento de San Martin | Peru | -8.38 | -76.30 | 2030 | 3560 |
| Milagro | city | Departamento de San Martin | Peru | -5.94 | -77.00 | 2588 | 3554 |
| Mirador | city | Departamento de San Martin | Peru | -6.82 | -77.71 | 7775 | 165 |
| Miraflores | city | Departamento de San Martin | Peru | -7.04 | -76.46 | 948 | 3176 |
| Miraflores | city | Departamento de San Martin | Peru | -5.90 | -77.04 | 2604 | 4854 |
| Miraflores | city | Departamento de San Martin | Peru | -5.91 | -77.37 | 3763 | 9605 |
| Misquiyacu | city | Departamento de San Martin | Peru | -6.79 | -76.26 | 954 | 3793 |
| Mono | city | Departamento de San Martin | Peru | -8.48 | -76.41 | 2286 | 2206 |
| Morales | city | Departamento de San Martin | Peru | -6.47 | -76.47 | 1387 | 15026 |
| Morroyacu | city | Departamento de San Martin | Peru | -5.83 | -77.02 | 2634 | 2235 |
| Moyobamba | city | Departamento de San Martin | Peru | -6.05 | -76.97 | 2375 | 1883 |