Abstract: A 3D numerical model combining the Re-Normalization Group(RNG) k-ε turbulent model,the buoyant correction and the non-linear Reynold stress model is developed to simulate density current,and suitable for solving the anisotropic flow problems.The evolution of the density current formed by temperature variance in reservoirs is simulated by the model.The simulated velocity distribution and temperature variation are compared well with the observations.The result indicates that the model can capture the nonistropical characteristics of the density current effectively,simulate the exact flow field as well as the temperature distribution accurately,and predict the time interval between the density current's stratification and diving process precisely.