The reinforced concrete beams which have been bending damaged are repaired by the six kinds of repair materials and its related methods. Based on the linear polarization method， the corrosion situations of the steel bars in the repaired concrete structures were studied， which were immersed in 5% magnesium sulfate. The results show that: different repair materials and its related methods， significantly affect the steel corrosion performance of patched members. The repairing method， cement-based repair mortar with zinc wire connected with the bar， can most effectively improve anti-corrosion ability of reinforced concrete. There is an exponential relationship between the polarization resistance and corrosion current density， and the relationship formula between the polarization resistance and corrosion current density was put forward.