Abstract: Heat resources are indispensable for agricultural environment and agricultural stabilization. Based on the daily air temperature data of 17 meteorological stations from 1980 to 2010, the heat condition was analyzed such as annual average temperature, diurnal range, annual accumulated temperature ≥0℃ and≥10℃, by using linear-trend estimate, moving average method, Mann-Kendall (M-K) method. The results showed that: the annual average temperature appeared upward trend in Linfen City, the rate of warming was 0.44 ℃/10 years, warming occurred mainly in spring and winter, the rates of warming were respectively 0.603℃/10 years and 0.49℃/10 years, the annual average temperature and climate tendency of the central plain was higher than the eastern mountains and the western mountains in the spatial distribution, and Linfen city was highest; the average daily range increased at the rate of 0.18 ℃/10 years; Linfen City, the annual accumulated temperature ≥0℃ increased at rate of 137.21℃/10 years, the annual accumulated temperature ≥10℃ increased at rate of 101.77℃/10 years; M-K test method derived, the annual average temperature and the annual accumulated temperature ≥0℃ increased significantly, the trend at the end of the 20th Century was higher than the significance level of 0.001, but the warming trend of the annual accumulated temperature ≥10℃ was only higner than the significance level of 0.05 after 2008.