In order to explore the change of soil enzyme activities of main plant communities under different soil environments in interdune lowland of Mu Us Sandy Land and their relationship with soil physical and chemical properties, 14 kinds of soil physical and chemical properties and 4 kinds of soil enzyme activities (catalase, urease, polyphenol oxidase, invertase) of 6 main plant communities (Phragmites australis, Juncus turczaninowii, Carex duriuscula, Puccinellia tenuiflora, Calamagrostis pseudophragmites and Salix psammophila) were measured, and their difference and the correlation between soil physical and chemical properties and soil enzyme activities of each plant community were analyzed. The results showed that: (1) Catalase activities of C. duriuscula and P. tenuiflora communities were significantly higher than those of S. psammophila and P. australis communities. There was no significant difference in urease activity among the six plant communities. P. tenuiflora and C. pseudophragmites communities had significantly higher soil polyphenol oxidase activity than other plant communities. Invertase activities of S. psammophila, P. australis and C. duriuscula communities were significantly higher than that of S. psammophila community. (2) There was a significant negative correlation between the activities of polyphenol oxidase and invertase, but no significant correlation between other soil enzyme activities was found. (3) The soil physical and chemical properties, including the content of HCO₃^-, Cl^-, K⁺, Na⁺, total P and pH, correlated significantly with hydrogen peroxide enzyme activity. Soil pH showed significant correlation with urease activity. The contents of soil HCO₃^-, Ca²⁺, total N, total C, total organic C and soil pH correlated with polyphenol oxidase activity significantly. Additionally, soil bulk density and soil organic C content showed significant correlation with invertase activity. On the whole, the soil enzyme activities of the main plant communities in interdune lowland of Mu Us Sandy Land were influenced by both plant community types and soil physical and chemical properties.