A new nonspecific protein antifouling polysulfone (PSU) material has been elaborated by grafting zwitterionic sulfobetaine (SB) complex by the means of PSU azidation (PSU-N3) followed by “Click-Chemistry” with acetylenic zwitterionic SB monomer (N,N'-diethyl-N-propargyl-N- (3-sulfopropyl) ammonium (DEPAS)). Azidation (PSU-N3) and functionalization (PSU-g-DEPAS) PSU materials were characterized by 1H NMR, Fourier transform infrared spectroscopy, and thermogravimetric analysis. Contact angle and protein adsorption on PSU-g-DEPAS and unmodified PSU membrane were studied. The results show that the chemical modification of PSU improved both the hydrophilicity and antiprotein absorption ability. This new fouling-resistance to protein material has potential for biomaterials applications. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41327.