Abstract: A pH-responsive hydrogel, which is synthesized by using mixed pectin and sucralfate treated with a small amount of acid to form a pH-responsive hydrogel. The pH-responsive hydrogel can form a temporary coating on the surface of the gastrointestinal tract to reduce excessive nutrient absorption, and exhibits excellent barrier properties and mucosal adhesion effects, which are useful for reducing blood sugar rise and weight gain, the liver fat accumulation, body fat accumulation and blood low-density lipoprotein that have a significant effect. In addition, the technical principles disclosed in the pH-responsive hydrogel should be applied to other polymer materials to manufacture different pH-responsive hydrogels.