NEW INFORMATION: The genus Aetius O. Pickard-Cambridge, 1897 is reported for the first time in China (Yunnan Province) and includes three species: one new species and two newly-recorded species. One new species is described, based on both sexes: A.maculatus sp. n. Additionally, A.bicuspidatus Yamasaki, 2020 and A.nocturnus Deeleman-Reinhold, 2001, are newly recorded from China, with photographs of habitus and genitalia being provided.