The genus Stenocephus is reviewed. A diagnosis of the genus and the differences between Stenocephus and its relatives are discussed and keyed. Stenocephus fraxini Wei, sp. nov., is described from China. Stenocephus oncogaster Shinohara, 1999, from Japan and S. Korea, and S. flavomaculus Wei, 2007, from China are redescribed. A key to known species of Stenocephus is also provided. Stenocephus oncogaster Shinohara is removed from the faunal list of China.