Simulium (Nevermannia) satakei sp. nov. is described on the basis of the pupa and mature larvae collected from the Ogasawara (Bonin) Islands in Japan. This new species, tentatively (due to lack of the adult stage) assigned to the vernum species-group of the subgenus Nevermannia, is characterized in the pupa by four gill filaments lacking transverse ridges, and in the larva by a small, M-shaped postgenal cleft, antenna without hyaline bands, and simple rectal papilla. The morphological differences among this new species and the two known species, S. (N.) uemotoi from Japan and S. (N.) karzhantacum from Uzbekistan and Turkmenistan, are noted. This is the second species of the family Simuliidae from the Islands.