A study evaluated a pilot-scale hybrid membrane photocatalytic reactor (MPR) using ZnO-Kaolin to treat polluted river water.ZnO-Kaolin was successfully synthesized and characterised using various methods, such as X-ray diffraction (XRD), fourier-transform IR (FTIR), and field emission SEM (FESEM).XRD and FTIR analyses verified the purity of ZnO-Kaolin, showing no impurities, while FESEM revealed ZnO nanoparticle growth on kaolin surfaces.Addnl., the ZnO-Kaolin band gap was shifted, demonstrating enhancement of photo-degradation efficiency.Optimization identified pH 5 as the most effective condition for treating the polluted Sembrong River via pilot-scale hybrid MPR integrated with ZnO-Kaolin, achieving significant removal of ammoniacal nitrogen (85.71%), COD (91.53%), BOD (84.93%), and suspended solids (99%).This innovative system also regulated water quality parameters, enhancing pH to 6 and dissolved oxygen to 6.3 mg/L while minimising membrane fouling.This innovative approach has promising potential for com.-scale water pollution control.