Abstract This work reports a novel polysulfone (PSf) membrane blended with a ternary copolymer having capsaicin-mimic moieties as an anti-fouling and anti-bacterial agent. This copolymer, P(H-M-A), was synthesized from N-(4-hydroxy-3-methoxy benzyl) acrylamide (HMBA), methyl methacrylate (MMA) and acrylic acid (AAc) by free radical polymerization. The effects of the P(H-M-A) content in the membrane casting solution on the structure and ultrafiltration performance of the membrane were investigated. It was shown that incorporating a small quantity of P(H-M-A) into the membrane improved the permeate flux and rejection when tested with a model humic acid (HA) solution and actual raw seawater. The P(H-M-A)-containing membranes exhibited excellent anti-bacterial activity, which was attributed to the capsaicin-mimic moieties, and their anti-fouling characteristics were demonstrated with fouling and cleaning experiments. This work suggests that P(H-M-A) is a potential hydrophilic anti-fouling and anti-bacterial agent for use in membranes for water applications.