The excellent potential of organic polymeric materials in the biomedical field could be exploited if their interfacial problem could be fully resolved. A necessary prerequisite to this purpose often involves the simple but effective synthesis of a bioactive surface to endow polymer surfaces with high reactivity toward efficient biomolecules conjugation and a bioinert surface to prevent nonspecific adsorption of nontarget biomolecules. Although the corresponding research has been an important topic, actually few strategies could pave the way to comprehensively and simply tackle both of the bioactive and bioinert surfaces preparation issues. Herein we report an extremely simple and integrative bifunctional method that could efficiently tailor an organic material surface toward both bioactive and bioinert functions. This method is based on the use of an amides-initiated photochemical reaction in a confined space, which depending on the type of solutes used, results in the incorporation of primary amine groups or surface carbon radicals on an inert polymer surface. The grafted amine group could be used as a highly reactive site for biomolecule conjugation, and the surface carbon radical could be used to initiate radical graft polymerization of. antifouling polymer brushes. We expect this simple but powerful method could provide a general resolution to solve the interfacial problem of organic substrate, offering a low-cost practical approach for real biomedical applications.