a b s t r a c tIn this study, the layer-by-layer (LbL) assembly method was employed to modify a commercial polyethersulfone (PES) membrane by successive adsorption of chitosan and alginate as cationic and anionic polyelectrolytes. To enhance anti-biofouling property, pure, PEG mixed and PEGylated AgCl/TiO 2 xerogels were incorporated solely in the top layer of the LbL-modified membranes. Organic and biological foulings were addressed separately using alginate and Escherichia coli bacteria suspensions as the organic and biological model foulants, respectively. LbL-modifying the commercial PES membrane successively with chitosan and alginate polyelectrolyte multilayers prevented organic fouling extensively. In addition, we found that AgCl/TiO 2 -incorporated membranes show higher water permeability and improved resistance to biological fouling as compared to the PES membrane. Silver amounts in consecutively collected permeate samples were quantified by ICP-MS analysis to assess the stability of AgCl/TiO 2 -incorporated layers. Silver loss per filtration cycle followed an increasing trend initially, up to a filtration volume totaling 3000 L/m 2 , leading to 4.2% reduction in the immobilized silver amount. After that, silver loss per filtration cycle stabilized at $ 7.44 μg/L, which extrapolates to $ 265 days time-span for the remaining silver to be released at a filtration rate of $ 1000 L/m 2 h. Antibacterial activity tests showed that AgCl/TiO 2 -incorporated layers do not permit bacterial growth on the membrane surface.