To investigate the change law of corrosion rate along the length direction of steel bars and its effect on mechanical properties of corroded steel bars, electrochemical acceleration corrosion experiments of concrete slabs were carried out. Results indicate that the non uniform corrosion steel bars can be obtained through use of direct current method by controlling the concrete density and immersing method of specimen. Furthermore, it is found that the yield load and ultimate load of non uniformly corroded steel bars under tension are more relevant with the maximum segment corrosion rate. And the value of parameter reflecting length characterization increases with average mass loss rate of corroded steel bars. Finally, the predicted loads expressed by the maximum segment corrosion rate are close to those of the experiments, which may be as references for other related researches.