As for large-scale ballistic simulation, traditional data solution costs much time and calculation, can hardly satisfy the requirement of fast operation response. In this article, an effective curve coefficient fitting method was put forward based on BP NN via constructing equation of main factors of ballistic curve and time, studying the relationship between equation coefficient and launching parameter, the missile curve was fit quickly. The simulation result shows that this method is more effective than the method of traditional data solution for calculating multiple trajectories.