Abstract: Gaozhou kudzu was as raw materials.Alkaline method was used to extract starch from Gaozhou kudzu.On the basis of the single factor experiments, conditions of kudzu starch extraction was analyzed through three factor ( liquid ratio, soaking time, pH value) three levels of the response surface methodology. The result of the starch extraction rate was as the date of response surface methodology. Design Expert software was used to optimize with the response surface for the rate of starch extraction from Gaozhou kudzu.And starch transparency, retrogradation, freeze-thaw stability, viscosity and other properties were studied with the extraction of starch.The optimized conditions were liquid ratio of 1 ∶ 4.5, soaking time of 2.0h, pH value of 10.2 soaking agent. Under the optimum conditions, kudzu starch extraction rate was 83.66%, the amylose content of 23.8%. The starch paste clarity and freeze- thaw stability was high, easy to coagulation. It belongs to the high swelling starch.6% starch paste viscosity at 95℃ for 15000mpa·s.