Abstract: In order to research the moisture adsorption and retention capacity of macromolecule pectin and modified pectin,the moisture adsorption and retention capacity of macromolecule pectin and modified pectin were determined under the conditions of 26 ℃,relative humidities of 20%,43% and 81%，the control sample were bone collagen and glycerin.The results showed that the macromolecule pectin and modified pectin exhibited proximal performance in moisture adsorption test as the bone collagen did，but worse than glycerin.The rentention capacity of macromolecule pectin and modified pectin were superior to bone collagen and glycerin.It is safe to draw the conclusion that macromolecule pectin would be a better moisturizing component than modifiedpectin.The moisture adsorption and retention capacity of pectin maybe has relationship with its molecular weight and esterifiable degree.

Key words: pectin, modified pectin, moisture adsorption, moisture retention