The invention relates to a liquid dressing containing a chitosan derivative, comprising the following components in percentage by weight: 1-5% of CMCS (carboxymethyl chitosan), 0.1-0.5% of collagen albumen powder, 10-15% of humectant, 0.2-2% of antibacterial agent, 2-10% of penetration enhancers and the balance of deionized water. The liquid dressing is obtained by mixing the components in sequence, stirring evenly and bulking. The liquid dressing has the advantage of good biocompatibility, good antimicrobial, antiphlogistic and hemostatic effects and high biological safety, and is convenient to use.