Agraeciini species from Hainan, China were investigated from 2017~2019. One new species, Nahlaksia hainanensis He Wang sp. nov., is described. Liara (Acanthocoryphus) brevis Ingrisch, 1998 and Mesagraecia gorochovi Ingrisch, 1998 are first recorded from Hainan, China. The COI genes of three species are provided and songs of L. (A.) brevis are first reported. The type species are deposited in Museum of Biology, East China Normal University (ECNU) and Shanghai Entomological Museum, Chinese Academy of Sciences (SEM, CAS).
Keywords: Orthoptera, conehead katydid, new species, song, COI, Hainan, China.