A model is a simplified representation of reality with which we can compute outcomes with-out having to perform actual experiments. Biophysical models predict the behaviour of the land use system in physical terms such as crop yields, environmental effects, and effect on management. ORYZA2000 model is an eco-physiological crop model to simulate the growth and development of a rice crop in situations of potential production, limitation and nitrogen limitations. In order to calibrate and validate the crop parameters of ORYZA2000 model, three years crop data was collected from research station and to simulate the rice yield under potential production for transplanted and rainfed rice. Results showed that the model over estimated yield of transplanted rice during the year 2007, while predicted well in yield of rainfed rice in Visakahaptnam district. ORYZA2000 simulated phenology of the crop very well and the corresponding results of phenology of two methods of rice were in agreement within the range of variation.