In order to fundamentally explain the repair mechanisms of realkalization technology for carbonated reinforced concrete, a real time Raman study was undertaken, on a simulated concrete/steel rebar interface without direct contact with the air and the electrolyte solution, to observe the evolution of corrosion products during realkalization treatment. The results indicate that the main corrosion product is green rust after artificial corrosion acceleration by impressed current. During the realkalization treatment, two reactions occur simultaneously, green rust is reduced into brucite(Fe(OH)2) and converted into magnetite(Fe3O4). The phenolphalein tests and the production of magnetite show that the realkalization technology can effectively increase the concrete alkalinity. The electrochemical measurements further indicate that the realkalization technology can effectively decrease the corrosion probability and corrosion activity of steel rebar to medium level, however, the steel rebars can not be repassivated.