[Objective] This article reviewed the mechanism of poly-γ-glutamic acid biosynthesis and its application to soil remediation and improvement, which was expected to provide references for further application to soil environment improvement and decontamination land remediation.[Methods] By reviewing domestic and foreign literatures, the synthesis mechanism of poly-γ-glutamic acid in different bacterial strains and their different roles in the restoration and improvement of soil environment were reviewed and analyzed.[Results] In this paper, poly-γ-glutamic acid was briefly introduced in terms of its physical and chemical character, molecular structure, biosynthesis and synthesis mechanism. The applications of poly-γ-glutamic acid to the improvement of arid soils, the remediation of saline alkali soil, the remediation of heavy metal pollution, the balance of soil PH value and the improvement of soil fertility soil were summarized in detail.[Conclusion] Some achievements have been made in the application of poly-γ-glutamic acid to soil remediation and improvement both here and abroad. In the future, it is necessary to strengthen the selection of high activity poly-γ-glutamic acid fermentation strains in different types of soil, as well as to focus the mechanism of interaction between poly-γ-glutamic and different types of soil materials.