The mud ball is made in by choosing the excellent pottery clay and adding to the pore-forming material, bonding clay, through the processes as, ball grinding, sieving, compacting, and calcinations. Its surface is hard, and there are many micro-pore pores among it. In addition, there are larger specific surface areas, higher porosity, and so on. During the wastewater treatment, there are many characteristics for this product, such as, the stronger capacity of the pollutant entrapment, lower loss of the pressure head, longer filtration period, and smaller water consumption of reverse washing. It is a sort of novel filtrating material, which can increase the output of water, improve the quality of water, and save the energy consumption.