Deionized water was applied to prepare five kinds of water samples, in which the organics were equivalent in contents, but different in polar components. Ultrafiltration membrane was used to filter the samples. Based on the filter cake and intermediate blocking filtration models, the effect of organic polarity on the membrane filtration performance was analyzed. The results showed that the removal rate of organic matters with different polarities was VHA>SHA>NEU>CHA. At the end of filtration, compared with initial fluxes, the fluxes of sample 1, sample 2, sample 3, sample 4 and sample 5 were 91%, 80%, 69%, 56% and 45%, respectively. The cake layer filtration resistance coefficient denoted by kpand membrane pore adsorption coefficient denoted by kcwere increased with the elevation of hydrophobic organic contents, indicating that both the deposition of hydrophobic organics on membrane surface and the membrane pore adsorption performance were stronger than hydrophilic organics. Hydrophobic organic matters were the major factors causing the organic pollution of ultrafiltration membrane.
