Abstract: Using soybean as raw materials, the pretreatment process for tartary buckwheat natto sauce production was optimized.The effect of different material pretreatment on the enzyme activity and quality of tartary buckwheat natto sauce was investigated, including different ratio of material to water, soaking time and boiling time.The optimal pretreatment conditions of tartary buckwheat natto Sauce were obtained through single factor and orthogonal tests.The results showed that:the ratio of material to water was 1∶3, the soaking time was 18h, the boiling time was 30min.Under this condition, the enzyme activity of paste was the highest, the taste and quality of tartary buckwheat natto sauce were much better, protease activity was 198U /g, glucoamylase activity was 85.94U /g, the amino acid nitrogen was 0.63g /100g, sensory score was 8.71.