Abstract: OBJECTIVE To introduce the traditional formulations, new technologies, new methods applied in the mucosal drug delivery systems. METHODS Review gels, sprays, aerosols, dry powder inhalations, microspheres, liposomes, nanoparticles, emulsion, in situ gel, absorption enhancers, bioadhesive agents, prodrug, enzyme inhibitors in the promotion of mucosal drug delivery systems. RESULTS Formulations, methods and techniques have been extensively studied, and progresses have been made in recent years. COCLUSION Mucosal delivery system has become a research hotspot and it has broad application prospects to replace the traditional delivery system. Exploitation of low toxicity and effective absorption enhancers and new drug carrier systems will be the main aspects to develop the mucosal drug delivery system so as to promote the penetration of the drug.