Biofouling of membranes in water treatment processes is considered a serious issue, as the presence of a few counts of microorganism cells can grow rapidly and cause serious performance disorders. Since it is difficult to remove all microorganisms by pre-filtering, the most effective way to reduce biofouling is to add a disinfectant prior to membrane treatment; however, incorporating bactericidal properties to the membrane surface (in order to prevent their growth) is desirable over adding disinfectants, as the latter may cause membrane deterioration. Thus, we are exploiting the bactericidal potential of quaternary ammonium acrylic polymers by grafting them on the surface of a polymer membrane. In order to achieve this, a quaternary salt of acrylic acid derivative, [2-(Acryloyloxy)ethyl]trimethylammonium chloride (AETMA) was taken and the polymerization on the membrane surface was done using UV initiation at 254 nm. Degree of grafting was found to be proportional to the monomer concentration and time of irradiation. We confirmed the chemical modification using ATR FT-IR spectroscopy by identifying a peak at 1660 cm-1 corresponding to the carbonyl stretch of the monomer. The streaming potential measurements show that the surface charge is reversed, with the zeta potential reaching a positive maximum of about 35 mV at 5 mins of irradiation for 3M concentration of AETMA. Interestingly, the pure water flux of modified 0.1 µm PES membranes at 10 psi increased substantially after the modification by about 30%. We are investigating on the solution flux and fouling of Escherichia Coli through the unmodified and modified membranes to compare performance. Further, the comparison of anti-biofouling properties of acrylic acid-modified membranes (negatively charged) with the AETMA-modified membranes (positively charged) is currently underway.