The genus Omiodes contains a radiation of 23 species of endemic Hawaiian moths, including some of the most adaptable of Hawaiian insects, as well as some of the most threatened. In order to explore diversification rates, host plant associations, taxonomic placement of the group, and validity of species within the group, we conducted phylogenetic analyses of 14 of the species based on three genes: cytochrome oxidase I, elongation factor 1α, and wingless. Low divergence rates suggest that the Hawaiian Omiodes are probably the result of a single, relatively recent colonization event to the Hawaiian Islands, followed by rapid diversification. There appear to have been frequent inter-island dispersal events and host plant shifts in the group. The Hawaiian species group closely to non-Hawaiian Omiodes, lending support to their placement within this genus.