Abstract: Salinization is a global ecological problem that seriously affects the development of agricultural productivity. Microbial inoculants can alleviate salt-alkali stress, enhance soil nutrient availability, and ameliorate soil salinization and alkalization. This paper elaborates on the current application status of microbial inoculants in the amelioration of saline-alkali soils and their impacts on soil microbial characteristics. It systematically reviews the mechanisms of action of microbial inoculants in improving the physical structure and nutrient availability of saline-alkali soil, regulating soil pH and ion content as well as soil enzyme activities, and affecting the morphology, physiology, yield and quality of crops grown in saline-alkali lands. Moreover, future prospects are put forward from four aspects, with a view to providing theoretical and technical references for the research and development of high-efficiency microbial amendments for saline-alkali soil amelioration.