The skin is the first barrier to maintain the stability of internal environment of the body and resist harmful factors of external environment, and is easily damaged because of various external factors. When full-thickness skin defects reach a certain level, it is difficult for the skin to repair itself, so wound dressings are needed to promote wound healing. Seeking an ideal dressing that can promote wound healing has long been a hot research topic. Chitosan is a unique biopolysaccharide polymer with good biocompatibility, biodegradability, antibacterial activity, and thermal stability, which has great potential in the development and application of wound dressings. Based on the introduction of properties of chitosan, this article reviews the role and mechanism of chitosan-based wound dressings in wound healing, and summarizes the hemostatic effect, antibacterial effect, delivery effect, and tissue regeneration promotion effect of chitosan, aiming to provide a certain reference for the research and development of new chitosan-based wound dressings in the future.