They live in moist to dry tropical forests. They are generally found close to the ground but rarely at ground level.

Biomes: tropical rainforest, tropical deciduous forest, tropical scrub forest

Neotropical: From southern Mexico to Panama

Unlike many marsupials, female Mexican mouse-opossums do not have pouches. Instead, females carry their young on their backs. Litters can be as large as thirteen, although most do not survive to maturity. Mothers generally eat those young that die in order to recapture some of the nutrients that they have invested.

This species generally eats insects and fruit but is also known to consume small rodents, lizards and birds' eggs.

The Mexican mouse-opossum is a nocturnal animal. They are generally found nesting under logs, in tall grass in trees and in small dense bushes, although they are also capable of making an underground burrow. They are sometimes found in abandoned birds' nests. Their primary predators are owls and snakes. Their social system is unknown but adults are not generally found together.

Like all animals that depend on tropical forests, this species is in decline due to habitat destruction.

They may eat some harmful agricultural pests, although it is doubtful that they have a significant effect on the density of those pests. They may occasionally eat fruits that are being cultivated near the forests in which they live, but probably not in large quantities.