A new species, Cheilolejeunea gaoi (Hepaticae, Lejeuneaceae) from Guangxi, China, is described and illustrated. It differs from other Cheilolejeunea species in its marginal denticulation of the leaf lobe and of underleaves. These are formed by projecting corners of two adjacent cells rather than single projecting cells. The new species resembles the genus Pictolejeunea in plant habit, leaf cells, perianth shape, absence of gynoecial innovation, and structure of apex of leaf lobule. However, the former differs primarily in the marginal position of the hyaline papilla of the leaf lobule and the absence of ocelli in the leaf lobes and underleaves.