A new species in the subgenus Simulium Latreille s. str. in the genus Simulium is described and illustrated. Simulium（Simulium） sanyaense sp. nov. is from the Sanya District on Hainan Island China. This new species is assigned to the tuberosum-group of the subgenus Simulium and is closely related to Simulium（S.） nitidithorax Puri（1932）, Simulium（S.） brevipar Takaoka and Davies（1995）, Simulium（S.） tianchi Chen, Zhang and Yang（2003）, and Simulium（S.） sigiti Takaoka and Hadi（1991）. However, it is differentiated from them by the genital plate, the enlarged sensory vesicle and the shape of cibarium in the female, and the pupal gill lacking a pit-like cuticular organ.
A new species, Simulium （Simulium） huangshanense sp. nov., is described based on the adult, pupal and mature larval stages collected from Huang Mountain in Anhui Province, China. This species is assigned to the griseifrons-group of the subgenus Simulium, and is morphologically most similar to S. （S.） grossifilum Takaoka ＆ Davies, 1995 from West Malaysia and S. （S.） hengshanense Bi ＆ Chen, 2004 from Hunan Province in China. However it is clearly differentiated from them by the shapes of the anterior gonapophyses and cocoon.
