The moss Syntrichia caninervis Mitt. is one of the dominant species in the biological soil crusts of desert. It has long been the focus of scientific research owing to the ecological value of S. caninervis has special significance for researching on its salt resistance. We investigated the changes in membrane structures of S. caninervis, and biochemical and physiological parameters under varying salt concentration gradients of NaCl (0, 200, 300, and 400 mmol/L) for 1, 2, 3, 5,7 and 14 days in this study. The results showed that it tolerated 200 mmol/L NaCl quite well. Electron micrographs of the fine structure of the cells were obtained, and no significant changes in electrical conductivity were observed at low salt concentrations. However, major changes in cell ultrastructure were observed at 300 and 400 mmol/L. Additionally, osmoregulatory substances and chlorophyll content reduced with increasing salt concentration and treatment time. In conclusion, S. caninervis has special morphological characteristics (e.g. the cell wall), which can enable it to survive in harsh salt stress environments and preserve the cell structure, while remaining intact after the release of NaCl stress; (2) During NaCl stress, a rapid and sustained increase in soluble sugars ("constitutive" protective substances) and free proline contributes to membrane (For example, the cell wall is thick and there is corner thickening phenomenon), enabling it to survive in harsh salt stress environments and preserve the cell structure, while remaining intact after the release of NaCl stress. Although it is not ecologically classified as a halophyte, our results suggest that it could be a novel plant model species to explore various aspects of salt stress.