The desert pocket mouse (Chaetodipus penicillatus) is a North American species of heteromyid rodent found in the southwestern United States and Mexico.

It prefers soft alluvial, sandy, or silty soils along stream bottoms, desert washes, and valleys, rather than rocky terrain.

These pocket mice live in soils that may be vegetated with creosote bush, palo verde, burroweed, mesquite, cholla and other cacti, and short, sparse grass, as well as in lower edges of alluvial fan with yucca, mesquite, grama, and prickly poppy.

Six subspecies are currently recognised:[4] Chaetodipus penicillatus may be active all year round in some areas, though it is inactive in the winter in southern Arizona.

Their burrows, however, are usually excavated in silty, sandy, or gravelly soil and are used for refuges, seed storage, and neonatal care.

It feeds primarily on seeds of forbs, grasses, and shrubs, although green vegetation and insects may supplement the diet.

Seeds of mesquite, creosote bush, and broomweed have been found in the cheek pouches of desert pocket mice.