Based on data from 19 bioclimatic variables under the current (1950-2000) and future (2050s, 2070s) climatic conditions with RCP45 CO_2 emission scenarios and on 132 distributional records of Didymodon in Xinjiang, we predicted the potential distribution of this genus in Xinjiang in the different periods by using the MaxEnt model and ArcGIS 10.2 software. Results showed that the major factors were mean temperature of wettest quarter, annual mean temperature, precipitation of driest quarter and annual precipitation, with relative contribution percentages of 33.6%, 22.2%, 16.4%, and 14.6%, respectively. For the simulation model with high accuracy, the AUC reached 0.84. For the contemporary climate conditions, suitable habitat of Didymodon accounted for 38.51% of the total area, with the most suitable distribution areas found to be the Tianshan Mountains, east of the Kunlun Mountains, and the Pamir Plateau. Compared to the present distribution, the suitable habitat distribution range of the genus will shrink in the future (2050s and 2070s); after shrinking, the suitable habitat area will account for 36.56% and 37.87% of Xinjiang's total area, respectively. Temperature and precipitation will likely be the important climatic factors causing the geographical distribution retreat of Didymodon. This research provides a reference for studying the effects of climate change on the species distribution of bryophytes in arid and semi-arid areas.