Seven new species in two genera, Sarcotragus and Bergquistia (Demospongiae: Dictyoceratida: Irciniidae), are described from Jeju Island, Korea. The separation of the two genera was made on basis of morphological evidence in skeletal structure, especially fasciculation of primary fibres and filament thickness. Two new species in the genus Sarcotragus and five new species in the genus Bergquistia are compared with other reported species.