The new species, Drepanolejeunea actinogyna J. Inuthai, R. L. Zhu & Chantanaorr., is described and illustrated from southern Thailand. The new species belongs in the subgenus Pristolejeunea Grolle because of the presence of median ocelli in the leaf lobe. It is closely related to D. thwaitesiana (Mitt.) Steph. and D. nymanii Steph., but differs in the smaller plant size, the radially-symmetric perianth with triangular wings equal in size and a 2–3 cells long beak of the perianth, the free lateral margin of leaf lobule proximal to the notch bordered by 4 rectangular cells, and the curved tooth of the lobule.