In order to analyze the relation between agricultural input factors and economic growth in Anhui Province, the evaluation index system of agricultural input is built from the perspectives of subject, object and tools based on grey system theory. The government investment in agricultural science and technology is selected as the index of labor subject, that is labor-related index（X1）, the total sown area of crops is selected as the index of labor object（X2）, the investment in rural water and electricity construction is chosen as the index of tools（X3）, and the GDP of Anhui Province is denoted by X0. According to the relevant data, the improved model of grey correlation analysis is adopted to calculate the correlation among the investment in agricultural water and electricity construction, total sown area of crops, government investment in agricultural science and technology, and the GDP in Anhui Province during 2004-2008. Results show that investment in agricultural science and technology contributes the largest to GDP growth, the increase and change of the total sown area and the investment in rural water and electricity construction have a weak correlation with GDP, they are in a less consistent development trend. On this basis, the government of Anhui Province further proposes to increase the investment in agricultural science and technology, enhance the protection of arable lands, keep the total sown area of crops, and properly maintain the rural water and electricity construction.