The cationic aqueous polyurethane (CAPU) coatings were prepared by reacting isophoron diisocyanate with quaternized diethanolamine (DEA) and poly(ethylene glycol) of two different molecular weights (M(n) = 600 and 1000 g/mol; CAPU(600) and CAPU(1000)). The quaternization of DEA and the formation of cationic polyurethane were investigated by Fourier transform infrared analysis. The pilling resistance and the antimicrobial property of the coated acrylic fabric were also studied. Obtained results showed that the pilling resistance of the treated fabrics increased with the increase in the concentration of the used CAPU. The acrylic fabrics treated with CAPU(1000) shows higher value of pilling resistance, even at lower concentration in comparison with CAPU(600). The higher the curing temperature is, the higher the pilling resistance, fabric roughness, and yellowness of the treated acrylic fabrics are. The untreated fabric showed no antimicrobial property, while the treated fabrics with CAPU showed superior antimicrobial properties. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 121: 777-783, 2011