Abstract: Sweet potato pectin was decolorizated with activated carbon, diatomite, ultrafiltration and ion exchange resin. The protein was hydrolyzed by protease. The result showed that better decolorization conditions were: activated carbon dosage 2.0%, temperature 50℃, time 40min. The reflux rate was 85% to 92% with ultrafiltration membrane decolorization. The process was simple and of low cost. The other small molecule was also removed during this process. It was also suitable for industrial continuous production.