A new salticid species of the genus Icius is described as Icius rugosus, from Mukojima, Anijima and Hahajima Islands of the Ogasawara Islands, Japan. This species resembles the generic type I. hamatus (C. L. Koch 1846) but can be distinguished from the latter by genital morphologies in both sexes and male chelicera with ventral wrinkles. Additionally, I. daisetsuzanus Saito 1934 is newly synonymized with Sitticus ranieri (Peckham & Peckham 1909), as Matsuda (1997) pointed out first. As a result, Japanese species belonging to this genus is only the new species for the present.