Abstract: Even though the water quality in natural river is polluted,the water power still exists and can be used.So we propose a method for air aeration using water power and appliedit to the aspect of sewage ecological treatment.The water quality standard will reach Ⅲ classification for surface water and the direct operation cost of sewage treatment will be greatly reduced in the polluted river water.The method abolishes the blast aeration (kinetic energy utilization),breaks down "The Sound Barrier" of sewage ecological treatment and brings the advantage of the water power utilization with cost low into full play.