Abstract: The purpose was to optimize the decolorization process of polyamide for gentian polysaccharide by response surface methodology. On the basis of single factor test, sample volume, flow rate and the concentration of polysaccharide from gentian were selected as influential factors. The comprehensive score(OD)including the decolorization rate and polysaccharide retention rate was used as response value. The response surface analysis was carried out by Box-Behnken to optimize the process of decolorization process of gentian polysaccharide. The results indicated that the optimal decoloration process conditions were as follows:the sample size was 5BV, the sample flow rate was 2BV/h, and the sample concentration was 3.50 mg/mL. Under these conditions, the decolorization rate of polysaccharide was 80.60%±0.91%, and the retention rate of polysaccharide was about 86.28%±0.67%. The predicted values of the model was 0.8756 and the score(OD)was about 0.8344, which showed a small error between both of them. After 5 times of reuse use, the decolorization rate decreased to 76.85%±0.30% and the retention rate of polysaccharide increased to 98.32%±0.37%. So the polyamide has a good recycling effect, and the optimization process is reliable.