【Objective】 This study aimed to explore the growth conditions of Echinochloa and its impact on soil nutrients under varying degrees of alkaline stress. 【Method】 Using the salinized sandy soil of the Mu Us area, this study set up five alkaline stress treatments based on the degree of salinization: pH 8.4, pH 9.0, pH 9.4, pH 9.7, and pH 10.0, with bare soil as control (CK). Growth dynamics and soil nutrient variations were monitored to evaluate the suitability of Echinochloa for vegetation restoration in alkaline degraded sandy areas. 【Result】 The results showed that when the pH increased from 8.4 to 9.4, the plant height and leaf area of Echinochloa did not decrease. However, a further increase in pH resulted in a significant decrease in plant height and leaf area. The treatment with pH 9.0 had the highest average number of tillers, followed by the treatment with pH 9.4. The net photosynthetic rate(P_n) and water use efficiency (WUE) of Echinochloa in pH 9.0 treatment were 26.39%-53.74% and 21.22%-36.36% higher than those in other treatments, respectively. After planting Echinochloa the content of soil organic matter (SOM) and nitrate nitrogen (NO₃^–-N) in the 0-10 cm soil layer significantly decreased, total nitrogen (TN) content in the 0-60 cm soil layer significantly decreased, whereas the ammonium nitrogen (NH₄⁺-N) content significantly increased. The tiller number and plant height of Echinochloa were significantly positively correlated with photosynthetic characteristics, and the root length density (RLD) was significantly positively correlated with the changes in SOM, TN, total phosphorus (TP) and available phosphorus (AP), and significantly negatively correlated with the change in NH₄⁺-N. 【Conclusion】 The pH 9.0 treatment promoted the growth of Echinochloa, however, growth of the above-ground part was hindered when pH was higher than 9.7, while root growth was hindered when pH was higher than 9.4. Cultivated Echinochloa mainly affected soil N nutrition, reducing the content of soil TN and NO₃^–-N, and increasing the content of NH₄⁺-N. These findings indicate that Echinochloa possesses strong alkaline stress tolerance and enhances soil nitrogen mineralization, confirming its suitability for vegetation restoration in alkaline degraded sandy soils of the Mu Us region.