Abstract: Ladou is a traditional fermented soybean product in China. Its taste is salty,fresh and moderate. It is rich in nutrients,but most of the beans are produced at home and are naturally fermented. There are some shortcomings,such as short storage time and poor taste,so this experiment adopted Bacillus subtilis,Bacillus amyloliquefaciens and Saccharomyces cerevisiae three strains to be used for the complex by Design Expert 8.06 software. The results showed that in the pH index,the inoculation group was significantly lower than CK group,in which sixth groups of pH was significantly lower than the other groups. The texture index of the inoculation group was significantly better than that of CK group. In terms of amino nitrogen,the inoculation group was better than CK group,and the content of free amino acids in the sixth groups was higher than that in the other groups. The sensory analysis showed that the sixth groups scored the highest. Comprehensive consideration,the sixth groups were selected as the best ratio,and the formula of composite bacteria solution was Bacillus subtilis:Bacillus amyloliquefaciens:Saccharomyces cerevisiae was 5.33:3.67:1.The purpose of this experiment would be propitious to improve the fermentation process of soybean wax by compound bacteria fermentation,improve the nutrition index of wax bean and promote the improvement of nutrition and health status of residents.