In arder to study Nitrogen and phosphorus removal from municipal sewage,simulation of artificial rapid infiltration land treatment system for nitrogen and phosphorus removal by using mixture medium in lab is made.The optimum operation mode is inrestigated for medium composition,flooding period and dry/wet ratio.It is shown that it is feasible to select soil/quarta sand,flooding period and dry/wet ratio as design parameter,and then to get optimum model through regressino statistics.