"In situ polymerization-blending" has been proved as an available approach to introduce capsaicin derivative containing two carbon-carbon double into membranes to enhance anti-fouling ability. However, conventional heating (CH) technique is expensive and time-consuming. In this work, a facile microwave assistance (MWA) approach was proposed for in-situ polymerization of antifouling polysulfone (PSf)/polyethersulfone (PES) and N-(5-methyl acrylamide-2,3,4 hydroxy benzyl) acrylamide (AMTHBA) composite membranes (PSf/PES-AMTHBA membranes) via phase-inversion process. This novel capsaicin derivative AMTHBA contains carbon-carbon double bonds enabled the self-polymerization process, moreover, it is also rich in hydroxyl radicals (-OH) that significantly improves the surface hydrophilicity. The resulting membrane exhibited the best performance in terms of water flux (up to 586.8 LMH) and rejection (98.5%), breaking the trade-off effect. In addition, PSf/PES-AMTHBA membranes also exhibited an outstanding antimicrobial activity with high efficiency (> 85%) and excellent resistance to bacteria (E. coli). The present approach would be time-saving and high-efficiently, encouraging its wider application in efficient water purification.