Abstract In this study, polypyrrole was prepared by in situ chemical oxidation polymerization and deposited on the surface of the PTFE membrane. The surface morphology of the membrane shown that the membrane fouling degree of the modified membrane was much lower than that of the original membrane. Besides, the contact angle value decreased from 107.20° to 72.62°, and its hydrophilicity was significantly enhanced. It took humic acid (HA) as a typical representative membrane foulants, and static and dynamic HA adsorption experiments were carried out on the membranes before and after modification. In the static adsorption experiment of HA, the adsorption capacity of an original membrane was 1.28 times that of a modified membrane. In the dynamic antifouling experiment of HA, the rejection of the modified membrane to HA was 62.99%, while that of the original membrane was only 39.82%. In addition, the experimental results showed that the modified membrane had a higher flux recovery rate, which was 1.18 times that of the original membrane. This study proves that the modified membrane has an extraordinary antifouling effect.