Abstract: Moss crust is the advanced stage of biological soil crusts and plays a vital role in the prevention of soil erosion and sand stabilization. In recent years, a lot of attention has been paid to these crusts because as a major component of desert vegetation, the ecology and function of biological soil crusts is crucial. In this study, distilled water and ethanol were used to extract different parts of Ephedra distachya (leaf, root and rhizosphere soil), and the extracts solution were added to glass dishes which had been filled with desert sand soil and moss fragments which were then cultivated. Growth indicators such as chlorophyll content, moss density, height and respiration were measured. The results showed that both water and ethanol extracts inhibited moss growth. As for different parts of extracts, leaf extracts showed stronger inhibition than root and rhizosphere soil. Respiration rate indicated that E. distachya extracts promoted CO₂ release from the moss crust, which resulted in the crust becoming sparse with any moss present being small. Compared with ethanol, moss crusts respiration treated with water extracts solution increased much more. The results suggest that there is an allelopathic effect from E. distachya on moss crust.