Fresno kangaroo rats eat mostly seeds, with small amounts of green vegetation and insects supplementing their diet when available. They forage for food frequently throughout a large home-range, sifting through the upper layers of sand and soil for fallen seeds.

Little is known about the Fresno kangaroo rat reproduction in the wild. Mating appears to begin in the winter. Most females seem to have one litter per year, although some have two or more. Young are born in burrows.

Fresno kangaroo rats have a short life span; they might only live between 10 to 12 months of age and rarely survive longer than three years.

The Fresno kangaroo rat has the smallest range of any kangaroo rat species in North America, potentially occupying only the central portion of the San Joaquin Valley, California. The Fresno kangaroo rat lives in arid areas and were once abundant across the valley floor, but transition of land to agricultural and urban uses reduced that habitat.

The Fresno kangaroo rat is one of three subspecies of San Joaquin kangaroo rats, distinguished by being smaller than the Tipton kangaroo rat (Dipodomys nitratoides nitratoides) and the short-nosed kangaroo rat (Dipodomys nitratoides brevinasus). The Fresno subspecies averages around 9 inches in length. Like other kangaroo rats, the Fresno kangaroo rat moves rapidly by hopping on its hind legs. Adapted to move in this hopping manner, the rat has long hind legs, a long tail, a short neck and a large head. They have four, rather than five, toes on their hind feet.