The invention belongs to the field of biological chemistry and concretely relates to an extracting and purifying method for amylase of lotus seeds. In order to solve the technical problems of complex step, relatively-low efficiency, long preparation period and difficulty in large-scale production of the existing extracting and purifying method for amylase of lotus seeds, the invention provides an extracting and purifying method for amylase of lotus seeds, which is simple in process, capable of easily realizing large-scale production and high in yield and purity. According to the extracting and purifying method for amylase of lotus seeds, lotus seed starch prepared from dry lotus seeds is used as a raw material, and the centrifugal speed and the concentration and the like of a NaOH solution are optimized, so that the aims of increasing the efficiency, shortening the operation time and favorably realizing large-scale production of the amylase of lotus seeds are achieved on the premise that the molecular structure of the amylase of lotus seeds is not destroyed; in addition, the purity of the extracted and purified amylase of lotus seeds is high (about 94%) and can be used as the standard of a method for measuring the content of the amylase of lotus seeds.