This study investigates the processing technologies of walnut soybean yogurt fermented by the mixed starter of Lactobacillus delbrueckii and Streptococcus thermophilus.The optimum processing technology is determined by orthogonal experiment: dry weight ratio of soybean and walnut 2∶1,incubation amount 3%,fermentation time 4.5h,weight of sucrose 7%,stabilizer 0.5%.The number of live bacteria of this walnut soybean yogurt processed under the above condition is 3.7×108 /ml.The change patterns of acidity,pH value and lactic acid bacteria number during storage were studied as well.