Abstract: Huidouba polypeptide from Huidouba protease hydrolyzate had been decolored by activated carbon powder.It was helpful to separate and purify the bioactive peptides by removing the pigment from Huidouba polypeptide hydrolyzate.Based on the results of single factor experiments, the decoloring process was optimized by response surface methodology. Activated carbon powder was the best as a bleaching agent and the optimal conditions were as follows: p H3.3, The amount of activated carbon 1.6%, temperature 44℃, time 53 min. Under the optimal conditions, the decoloring rate was 73.12%, and the peptide retention rate was 82.49% which were close to theoretical value. The decoloring process was cost- effective, simple, reliable, and maximized the retention of Huidouba protease hydrolyzate with high peptide retention rate.The results would provide a theoretical foundation for the development of Huidouba polypeptide.