Based on observed meteorological data from 508 stations in China, the distribution characteristics of heat resources were analyzed by using climatic trend rate and GIS methods in national scale in recent 50 years (1961-2010), and the change characteristics of heat resources between two periods (period I 1961 -1980, period II 1981-2010) were compared. The results showed that the heat resources distributed unevenly, and more heat resources in southern China than that in northern China. The key influence factor in eastern China was latitude, while topography was key factor in western China. Counter lines of average daily temperature 0℃, 10℃ and 15℃ in period II moved northward comparing with period I, days of average daily temperature≥0℃ and ≥10℃ increased 5. 5d and 4. 7d on average, respectively. The distribution and change of average daily temperature ≥0℃ was similar to that of accumulated temperature≥ 10℃. The areas of the accumulated temperature zone of 5500-6100℃ ?d (≥0℃ accumulated temperature) and 5300 -6500℃ ?d (≥10℃ accumulated temperature) increased by 5. 32 * 10~4km~2 and 1. 92 * 10~3km~2, respectively. The climatic trend rate of average temperature was 0. 27℃/10y in 1961 -2010, and the climatic trend rate of maximum and minimum temperature was 0.37℃/10y and 0. 21℃/10y in northern China. The accumulated temperature ≥0℃ and ≥10℃. increased 70℃ ? d/10y. The heat resources (mean temperature, minimum and maximum temperature, accumulated temperature) in China showed a increasing tendency in recent 50 years, and minimum temperature played a major role on climate warming, whose variation degree was larger than that of maximum temperature. Climate warming might have some impacts on agricultural production and agro-climatic zone (including introduction, maturity-type shift and planting area expansion, etc.). The research result was helpful to determine the appropriate agro-climatic indexes and crop cultivation area.