The climatic production potential in Inner Mongolia was assessed by the annual temperature and annual precipitation from 1961 to 2016 based on Miami and Thornthwaite Memorial model. The spatiotemporal variation feature of annual temperature, annual precipitation and climatic production potential (CPP) were analyzed. By sensitivity tests, the potential changes of CPP under different meteorological factors variation were simulated. The results showed that regional differences of annual temperature and precipitation in Inner Mongolia were both significant. In the past 56 years, the warming trend was significant and 97% of the region had an increasing precipitation(P<0.01).Precipitation was fluctuating while the trend of linear change was not significant. The CPP showed the zonal distribution of southeast-northwest and regional differences were significant. But the trend of linear change of annual CPP was not significant except Hulunbuir(P<0.05). The CPP was more sensitive to precipitation, which means with the warming trend in Inner Mongolia, its changes determined on the precipitation in the future. The grain yield and the climate resource utilization were gradually improved and there was still space for crop yield increase in the future. However, sustainable development should be taken into consideration, and use climate resources more reasonable.