Interfacial modification of proteins refers to modifying interfacial proteins during the post-emulsification stage to enhance the thickness and rigidness of interfacial protein films and consequently improve the physicochemical properties of emulsions. Moreover, interfacial modification of proteins can avoid some of the adverse effects of pre-modified proteins before emulsification on emulsion properties. However, in-depth research and a systematic summary of the existing research on interfacial modification of proteins are still lacking up to now. Therefore, this article reviews several widely used methods to modify interfacial proteins, such as enzymatic cross-linking, polysaccharide modification, polyphenol modification and oxidative modification, with special reference to their principles and effects on improving emulsion properties. Besides, future development directions are discussed, with the aim to provide a theoretical basis and technical support for further improving the physicochemical properties of emulsions.