The half cell potential, linear polarization, Tafel curves and electrochemical noise measurement were used to study the effects of cathodic protection of reinforcing steel in simulated concrete pore solutions with thermoelectric generator as power. The results indicate that thermoelectric generation unit has the same properties with DC power and internal resistance would not greatly vary with temperature differences. In addition, thermoelectric generation unit exhibits good stability in cathodic protection system and potential of rebars has a negative shift to protective potential with cathodic protection current. Corrosion current and electrochemical noise tests show that corrosion rate decreases greatly and rebars turn to thermodynamic stability from corrosion state. With the same protection current, rebars show better corrosion resistance performance in medium with lower concentration of chloride ion.