A phylogenetic analysis of the leafy liverwort genus Mesoptychia (incl. Leiocolea and Hattoriella), using two chloroplast markers, rbcL and rps4, was performed to clarify the circumscription of the genus and to establish its systematic position within the Jungermanniales. Ten species and one variety of Mesoptychia (out of a total of 17 accepted specific names), together with 85 species from 57 genera representing different lineages of Jungermanniales, were sampled. The results support the monophyly of Mesoptychia and its inclusion within the Jungermanniaceae, which itself forms a clade with the Delavayellaceae. Gymnocolea borealis, previously treated under Leiocolea (= Mesoptychia), is nested in the Anastrophyllaceae. The synonymy of Hattoriella with Mesoptychia is phylogenetically confirmed. Four major clades are identified within Mesoptychia and their circumscriptions and distinguishing morphological features are discussed.