In order to make the most of tomato in Xinjiang, we study the extraction technology of tannin from the tomato stems and leaves with ultrasonic method. The contents of tannin was taken as evaluation indexes to determine the optimum extraction technology. Selecting the four factors which are ethanol concentration, solid-liquid ratio, ultrasonic time and ultrasonic number as orthogonal experiment on the basis of the single factor experiment. The results showed that the best extraction conditions of each experi...