Abstract: Based on the indexes of spring frost damage grades of corn, the authors built the statistical relationship between ground temperature and air temperature, and fitted the ground temperature data of township, then carried out the refined risk assessment of spring frost disaster-causing factors of corn in Baiyin. The results showed that: the later the occurrence time of spring frost in Baiyin, the stronger the intensity of frost, and the more serious disaster degree the frost caused to crop; during the study period, there was a significant correlation between ground temperature and air temperature, the temperature of regional station and local station, the high reliability of ground temperature in township was fitted; from the distribution of the whole frost intensity grades, there was always a high value area in northwest Jingtai, because of relatively low altitude and topographic factors, there was a weaker intensity of frost in Baiyin and Jingyuan; from the probability distribution, the higher probability of spring light frost disaster appeared in Huining and Jingtai, the medium frost disaster mainly appeared in Baiyin and Pingchuan, however, the higher probability of heavy frost disaster appeared in Jingyuan; from the risk index, the high risk area of spring frost disaster in Baiyin was mainly in western Jingtai and Baiyin, where the risk index exceeded 0.32; the risk index in north central Huining was relatively low, and was about 0.2 in most of the township.