Current floristic research in Korea has resulted in the recognition of a new variety of Geranium koraiense Nakai. A new variety, Geranium koraiense var. chejuense S.-J. Park et K.-J. Kim from the Jeju island in Korea is described, illustrated and compared to its typical form. The new variety is easily distinguished from G. koraiense var. koraiense by its clefted petal apices, larger flower size, densely distributed trichomes on stem, and longer and trichomed stylar portions of fruit. A key to G. koraiense var. koraiense and G. koraiense var. chejuense is provided.