The Natal multimammate mouse (Mastomys natalensis) is a species of rodent in the family Muridae.

[1] The Natal multimammate rat is the natural host of the Lassa fever virus.

[2] Its natural habitats include subtropical or tropical dry forest, subtropical or tropical moist lowland forest, dry savanna, moist savanna, subtropical or tropical dry shrubland, subtropical or tropical moist shrubland, arable land, pastureland, rural gardens, urban areas, irrigated land, and seasonally flooded agricultural land.

These rats are closely associated with humans, and are commonly found in and around African villages.

It has great value for researchers studying stomach cancer and spontaneous tumors.