Currently, crop modeling is a useful tool for simulating crop output and growth under various agronomic practices. It also can used to evaluate the impact of these managements on the environment such as greenhouse gases i.e. N2O, CH4, CO2, N, NH3 and the transport of carbon, nitrogen, water and pesticide in soil at upper or deeper depth levels. Recently, the DSSAT 4.8 version integrated a pest growth module too which will help to stimulate the growth of pest during the crop growth period. Further, crop simulation models are integrated with forestry or tree models and now these can used for carbon sequestration purposes to reduce the carbon concentration from the atmosphere and restore into soil. Hence, crop modelling technic have a lot of scope to work to maintain the environment without affecting crop production for a global population.