Through putting protein additives in reactive dyes wastewater and decolorization, both of the additives and dye wastewater changed into a kind of complex compound. Protein additives with amorphous loose micelle structure which has -NH2, -COOH, -OH and -CONH- produce electrostatic attraction, hydrogen bonding, van der Waals force and hydrophobic interaction between dye ions and dye molecules. Thereby, absorptive dye can embed dyes in micelles by adsorption, flocculation, coagulation to achieve the collecting of dye in dye wastewater. In this paper, we mainly discussed the performance and reuse of decolorized dyes. Further we studied on the reuse of the protein blends dye and the use of WLS for cotton fabrics pretreatment. By researching on the influence of WLS amount, optimal process conditions including pretreatment, dyeing, were both determined. The effect of WLS modification was also evaluated. It was found that the dyeing rate in decolorized dye increased after cotton was modified by WLS. Therefore, it is necessary to explore the decolorization of reactive dyes wastewater and the reuse in order to save dyes, chemicals and reduce emission.