Ancient processing technology of Pinellia ternata: take out impurities, divide them into sizes, soak them in clear water until the inside is dry, then soak them in 8% alum solution until they taste slightly numb, take them out and wash them, cut them into thick slices, and screen out impurities. In the processing method of Pinellia ternata in China Pharmacopoeia, needle-like crystals of calcium oxalate, the toxic component of Pinellia ternata, are insoluble or hardly soluble in water, while the effective component is easily soluble in water. Its detoxification mainly depends on the auxiliary materials, which leads to the low yield and extract content of processed Pinellia ternata, and the toxic components are not completely removed during the processing, which can not guarantee the quality of processed Pinellia ternata.