Chitosan is the second abundant natural polymer after cellulose and shows a lot of potential functional advantages such as biodegradability, biocompatibility, antimicrobial properties etc. Cotton knit/chitosan sponge composite structures were prepared by coating chitosan solutions ($CH_3COOH$, HCI) onto the cotton knit fabrics, freezing at $-80^{circ}C$, and Iyophilizing. Chitosan in two kinds of salts solutions was crosslinked with glutaraldehyde and citric acid prior to coating. Knit/chitosan sponge structures were transformed into the hydrogel structure when they absorbed water. 2% chitosan acetate composite crosslinked with citric acid absorbed water about 23 times of its dry weight. Weak physical properties of Iyophilized chitosan sponge were improved by forming knit/chitosan composite structure.