This product is a high-performance fixing agent for reactive dyes composed of the main components of cationic polymer compounds. It has an extremely good effect on improving the wet fastness of natural fiber dyed products such as cotton yarn (cloth), Rayon, Silk and other general cellulose fibers. After the product is fixed, there is very little change in hue and decrease in fastness to sunlight. Especially, it has obvious upward function on the fastness to chlorine resistance (20PPM strong chlorine test).