We record a tree frog of the genus Liuixalus for the first time from outside of China and describe it as a new species, Liuixalus catbaensis, on the basis of a single juvenile specimen collected from Cat Ba Island, northern Vietnam. The new species is easily distinguished from all other members of the genus Liuixalus by its uniformly brick-red dorsum lacking dark markings. The biogeographical significance of finding of this species in Vietnam is briefly discussed
