Abstract: Considering the kinematic characteristics of streamflow and cooling water, and based on the control equations of cooling water in the non-orthogonal curvilinear coordinate, a 2-D mathematic model for cooling water is presented with non-staggered grids in the non-orthogonal curvilinear coordinate.This model is used to simulate the movement of cooling water of an electric power plant in a natural channel. Calculation results show that the model can reflect rationally the movement of cooling water of the electric power plant.