Reimersia inconspicua (Griff.) P.C.Chen known from China, Taiwan, India, Nepal and the Philippines is newly reported from Myanmar. Based on the Myanmar material, a morphological description, illustrations and ecological information are provided. The species is characterized by stems showing a triangular cross section, with trifarious leaves; sheathing leaf base with a series of elongate cells adjacent to the shoulder margins, shorter and wider cells in the juxtacostal region; and distantly dentate upper leaf margins. The phylogenetic relationship within the genus Reimersia is inferred based on nuclear ITS sequences. The genus was resolved in the clade corresponding to the tribe Pleuroweisieae (Pottiaceae), while the two Reimersia species are not resolved as a sister relationship. This suggests that the unique morphological characters circumscribing the genus have originated from convergent evolution.