Lactic acid bacteria (LAB) is widely used in food and food fermentation industries. Among them, acid whey tofu with LAB as coagulant has gradually obtained more and more attention. LAB is the dominant bacteria in the fermentation process of acid whey tofu, which was inevitable above 75℃ during the pasting process of acid whey tofu. Ordinary LAB cannot tolerate this temperature, and a large number of inactivation at this temperature will affect the ripening of the product. In order to develop high temperature resistant LAB, four strains of high temperature resistant and acid producing bacteria were screened by ultraviolation mutagenesis with the strains isolated from Jianshui acid tofu whey in Yunnan province. The results showed that the four strains could resist high temperature at 75℃ for 30min, and maintained a good activity and acid-producing ability. Compared with the original strain, the mutant strains obtained in this study had better temperature resistance and acid-producing ability. Among them, HCUL 1.1801-1912Z had the best activity and acid-producing ability and it will significantly improve the quality of acid whey tofu. The activity of the LAB in the tofu and tofu quality can be obviously improved.