Under badly environmental conditions as well as complex loads, corrosion of embedded reinforcing steel bars
in concrete is common for reinforced concrete (RC) structures. Fatigue of corrosion reinforcing steel bars is a key problem
for old RC bridges. To assess the residual fatigue life of aged existing RC bridges, the most new study information on
fatigue of natural corrosion reinforcement is analyzed, and axial tensile fatigue tests are conducted on fifteen naturally
carbonation-induced corrosion steel bars. The fatigue test results indicate that the existence of corrosion pits reduces the
fatigue life of steel bars significantly under the same fatigue stress; with the development of corrosion, the fatigue life of
steel bars decays according to negative power exponent law approximately and the attenuation rate increases with stress
level augment. For the complexity of fatigue and corrosion, further pertinent conclusions remain to be confirmed.