An antimicrobial cationic reactive dye was synthesized by reacting aminoanthraquinone with cyanuric chloride, 3-dimethylamino-1-proponol, and lauryl chloride in sequence. The chemical structure of the dye was fully characterized by using H-1-NMR, C-13-NMR, and FTIR analysis. This dye demonstrated adequate antimicrobial properties in aqueous solution. The minimum inhibitory concentration of the dye against bacterial concentrations of 10(6)-10(7) colony forming units (CFU)/mL of both E. coli and S. aureas were only 10 ppm. The dye can react with cotton without addition of any salt as electrolyte. The dyed fabrics showed proper color washing durability. But the antimicrobial functions were severely affected by laundry. (c) 2008 Wiley Periodicals, Inc.