Abstract: Administration oral mucosal drug delivery has the advantages of high patient acceptance, rapid onset of action, convenient, etc., and it can avoid the first-pass effect of the drug in the liver. Nevertheless, the design of oral mucosal drug delivery systems is inherently challenging due to the distinctive physicochemical properties of certain drugs and the specific physiological environment of the oral cavity. Natural polysaccharide chitosan-based materials exhibit favorable characteristics, including non-toxicity or low toxicity and biodegradability. These materials can effectively inhibit bacterial growth, enable controlled drug release, and enhance mucosal adhesion. Consequently, chitosan-based materials have been the subject of extensive research in the field of oral mucosal drug delivery systems. This paper offers a comprehensive overview of oral mucosal drug delivery systems, reviews relevant studies on chitosan-based materials, and discusses future prospects for their application.