Several models (quadratic,square root, linear+plateau, quadratic+plateau) used for describing crop yield response to N fertilizer at winter-wheat and summer-corn rotation are compared. Data from four experiments which were conducted at Beijing and Henan province are used. All models fit the data equally well evaluated by using the R² statistic, but using linear+plateau model can reduce optimum N rate, increase economic profit of N fertilizer at the premise that crop yield don't reduce. Analyzing from environmental factor, linear+plateau model can maintain the balance of soil inorganic N, improve N fertilizer recovery, reduce crop straw N content and the emission of NOx by straw burning. So, linear+plateau model is the most suitable model in winterwheat and summer-corn rotation system in north of China.