The world fauna of the genus Thricops Rondani is revised. Forty-four valid species and two subspecies arc recognized in the present study. All species arc described and genitalic illustrations Liven for both sexes. Six new species arc described, four from the Palaearctic realm (T. angelorum sp. n., T nigriabdominalis sp. it., T ponti sp. n.. T. vaderi sp. it.) and two front the Nearctic realm (T. aduncus sp. it., T. dianae sp. n.). The oriental species T. ilamensis Shinonaga and the Palaearctic species Azelia fengi Fan arc excluded from the genus and the Nearctic T medius (Stein) is synonymized with T villicrus (Coquillett). Keys for each sex are given, and knowledge on the biology of most species is summarized.