Abstract: There are a large number of challenges in ophthalmic drug delivery because of the complex anatomical structures and the special protective barriers of the eyes. However, there is no doubt that the traditional ophthalmic preparation generally meet key problems with large dose loss and short residence time. The intraocular bioavailability of the drugs can be promoted by improving the retention performance of the drugs in the eyes. On the one hand, there are a great of mucosal adhesion polymers to modify the preparation, such as chitosan and its quaternary ammonium derivatives, polyethylene glycol, hyaluronic acid and carbomer and so on, which can enhance the adhesion between the preparation and cornea. On the other hand, researchers can utilize the interaction between nanodrug delivery system and in situ gel system and ocular mucosa, which is extremely good to lengthen the residence time of the drugs on the surface of the eyes. Therefore, in this paper, based on the improvement of corneal retention performance of drugs, the novel ocular drug delivery systems and bioadhesive materials that can modify the performance of preparations are reviewed for the purpose of providing effective reference for the treatment of ocular diseases with new materials and new preparations.