The long-billed partridge (Rhizothera longirostris) is a species of bird in the family Phasianidae.
It is found in the Malay Peninsula, Sumatra and Borneo. Its natural habitats are subtropical or tropical dry forest, subtropical or tropical moist lowland forest, and subtropical or tropical moist montane forest. It is threatened by habitat loss. There are two distinct subspecies; the nominate race R. l. longirostris is relatively widespread, while R. l. dulitensis, sometimes considered to be a full species known as the Dulit partridge or Hose's partridge (R. dulitensis), has a very restricted range in the mountains of central Borneo.