Abstract
Two new species of Hainanphasma Ho, 2013, Hainanphasmalongiacuta sp. nov. and H.longidentata sp. nov., are described and illustrated based on specimens of both sexes from Hainan, China. The heads of H.cristata Ho, 2013, based on both sexes, and H.diaoluoshanensis Ho, 2013, based on females, are redescribed from new materials. The generic diagnosis of Hainanphasma is improved, and the distinction from Orestes Redtenbacher, 1906 is clarified. The male and egg of H.diaoluoshanensis are described and illustrated for the first time. A key to species of Hainanphasma is provided.