A new species group of the genus Lilioceris Reitter, 1913 is proposed and keyed as neptis group, characterized by adults with mesoventral process widened, tuberculate, and horizontally connected with mesoventrite. It includes six species: Lilioceris balyi Ch?j?, 1962, L. cantonensis Heinze, 1943 stat. rev., L. fouana Pic, 1932, L. neptis (Weise, 1922), L. subpolita (Motschulsky, 1861) and L. vietnamica Medvedev, 1985. Among them, Lilioceris cantonensis Heinze, 1943 is resurrected as a valid species from synonyms of L. neptis (Weise, 1922); L. fouana Pic, 1932 is transferred from the subgenus Chujoita Monrós, 1959 to the subgenus Lilioceris Reitter, 1913; L. vietnamica Medvedev, 1985 is firstly recorded in China; some misidentifications of former literatures for L. neptis are provided. Redescriptions (if necessary), habitus photographs, geographic distributions, host plants and habitats (if known) are provided for these species.