Abstract: Aiming at defects of large tuber broken area，high dissociation rate from starch and its nutrients，and loss of potato flavor substances in traditional pulping method，raw potato pulping machine with double shear and sequential breaking function was optimized by mechanism research and structure design，and relevant performance tests were carried out.Results showed that，starch dissociation rate could be effectively reduced by using double shear breaking technology，pulp particle size decreased with increase of speed of cutting tool head during double shear breaking，hole size of sieve had great influence on pulp particle size and starch dissociation rate.