Based on the daily meteorological data of 6 sitesfrom 1971-2013, have analyzed the climate variation in Hilly Area of Central Sichuan, and researched the effects of climate change on potential productivity of spring maize by a case study in Suining Region. The results indicated that: (1) The variation coefficients of yearly sunshine hours and precipitation was 14.79% and 18.71% respectively, and the annual difference was obvious. Also the sunshine hours have been assumed a decreasing trend year by year, the climate tendency rate of sunshine hours was -72.69 h·10a~(-1), while there was no big annual difference for the yearly mean temperature and relative humidity. (2) The variation of sunshine hours, precipitation, mean temperature and relative humidity in growing period of spring maize were matched with the yearly climate change,the annual variation of sunshine hours and precipitation in growing period of spring maize was more obvious. (3) Both the photo-thermal potential productivityand climatic potential productivity of the spring maize in research area has assumed a decreasing trend. There was extremely significant correlation between photo-thermal potential productivity and sunshine hours with the temperatures, while the climatic production potential had an extremely significant correlation with the sunshine hours and relative humidity, and a significant correlation with precipitation. So the sunshine hours was the primary limiting factor for the photo-thermal potential productivity and climatic potential productivity in this area, also the precipitation and relative humidity were the key factors for restricting climate potential productivity of spring maize.