Abstract: In order to predict the frost in orchard, improve the frost effect, predicting the lowest temperature and the time its occurrence in apple orchard is very critical. Based on the temperature observation data in Taolin Horticultural Field of Ningxia and meteorological data of Yinchuan meteorological stations, temperature variation characteristic was analyzed and the temperature relation model of Yinchuan meteorological stations and orchard was set. The results showed that: the daily minimum temperature in orchards of spring in the state of fluctuation, the minimum closed to -12℃, the maximum up to 12.4℃. The day in spring which minimum temperature reached 0℃ was totaled 29 days, the temperature below 0℃ would affect blossom, fruiting of fruit trees. In spring the daily minimum temperature mainly occurred at 5:00, 6:00 and 23:00 in the sunny, cloudy, rain (snow) days. The daily minimum temperature in orchards of autumn decreased increasingly, the minimum close to -13℃, the maximum up to 16℃, some time the temperature may have some effects on fruit quality. In autumn the daily minimum temperature mainly occurred at 7:00, 8:00 and 23:00 in the sunny, cloudy, rain (snow) days. The minimum temperature in orchard and Yinchuan meteorological stations minimum temperature was liner relationship, and forecasting equation of the daily minimum temperature in orchard was established. The results of history back substitution showed that two forecasting equations were good accuracy: most absolute errors were less than 2℃. The results could provide basis for fruit frost monitoring and defense. The results could provide of, and it would have important significance to draw on the advantages and avoid disadvantages.