Abstract: In order to explore the relationship between the climatic resource and yield of grain, based on date of sunshine duration, temperature and precipitation in seven weather stations in Tianshui from 1961 to 2010, the author analyzed the variation law of agrometerological resource with the methods of rate of climate change, Mann-kendall and Z-score standardization. The results showed that: the annual sunshine duration decreased by 30 hours every 10 years. The annual mean temperature, average maximum temperature and average minimum temperature increased by 0.40℃, 0.36℃ and 0.39℃ every 10 years respectively. It also indicated that the annual precipitation decreased by 20 mm every 10 years. The comprehensive natural resource index varied with curve of the second degree and the turn point was at 1982. It decreased by 0.08 every 10 years from 1961 to 1982 and increased by 0.48 every 10 years. This variation met with the yield of grain at research area.