A new species of the proturan genus Eosentomon, E. rishir, is described from Rishiri Island, Hokkaido, northern Japan. The present species is characterized by the position and/or shape of sensilla c' and b on the foretarsus, the absence of A5 on abdominal tergites IV-VII, and the position and shape of P1a on tergites II-VII. An updated key to the Japanese species of Eosentomon is presented.
