Tokudaia is a genus of murine rodent native to Japan. Known as Ryūkyū spiny rats or spinous country-rats, population groups exist on several non-contiguous islands. Despite differences in name and appearance, they are the closest living relatives of the Eurasian field mouse (Apodemus).

Named species are:

  • Muennink's Spiny Rat, Tokudaia muenninki
  • Ryukyu Spiny Rat, Tokudaia osimensis
  • Tokunoshima Spiny Rat, Tokudaia tokunoshimensis

At least Tokudaia osimensis may be a cryptic species complex.