Resistant starch (RS) has various functions in controlling the glycemic index (GI), lowering concentration of cholesterol and triglycerides, inhibiting fat accumulation, preventing colonic cancer, reducing gall stone formation, maintaining intestinal tract healthy and enhancing the absorption of minerals. Elevated RS in food is an important and effective approach for public health. RS is also an important material for industries. In this paper, the producing technologies of resistant starch from buckwheat were investigated. The results showed that the optimum parameters for producing technology of resistant starch from buckwheat using hydrochloric acid (HCl) hydrolysis treatment are heating temperature after HCl hydrolysis at 120℃, HCl concentration 3%, solid-to-liquid ratio after HCl hydrolysis 1:5, heating time after HCl hydrolysis 0.5h.