EPS are widespread in the internal and surface activated sludge flocs, constitute a bridging role between cells, cells of matter and energy through the extracellular material, have important physiological functions. The MBR membrane flux decline rather than that of supernatant fluid mainly from sludge colloid and soluble organic matter; EPS concentration and the influence of the sludge mixture hydrophobic, Zeta potential, viscosity, particle size and other physical and chemical properties and biological activity of zoogloea, good relation with membrane fouling degree; Through the adjustment of operating conditions can change the composition and content of EPS, ensure the normal operation of sludge system while maintaining good membrane flux.