The corrosion resistance of bainitic steel was compared with a weathering steel 09CuPCrNi through accelerated corrosion tests. The results indicated that the corrosion resistance was better for bainitic steel than 09CuPCrNi based on the weight loss. The characteristics of the rust layers indicated the rust layers on two steels are composed of two parts: the loose outer rust layer and the dense inner rust layer. The rust layers are mainly composed of goethite (α-FeOOH) with a few of lepidocrocite (γ-FeOOH). The factors including homogeneous microstructure and lower carbon content played important roles in enhancing the corrosion resistance of bainitic steel.