One of possible impacts of global warming and climate change on agricultural systems is shift in growing season length which would affect crop yield and water requirements. For crops like maize with variety planting dates, as an adaptation measure can help in optimum water consumption management. In current study the SSM Crop model was used to investigate the effect of different 7 planting dates scenarios with 15-day interval starting from April 20^th for both rainfed and irrigated maize, with each Climate change trend during a 32 years period was analysed during the growth period using statistical tests in the Gorgan region. The results demonstrated a decrease in precipitation and an increase in temperature of approximately 1°C[N1] , …in region which means more aridity, and consequently increased irrigation water requirements by about 3.5 mm per year. In rainfed cultivation, evapotranspiration decreased due to precipitation shortage, whereas in irrigated cultivation, evapotranspiration has increased as a result of maintained irrigation demands. Under the observed climate change, maize yield and water use efficiency have significantly declined in both rainfed and irrigated crops. Therefore, to mitigate these impacts under full irrigation, early planting is recommended, while for rainfed cultivation, either early planting or the latest planting dates are recommended.