Abstract: The atmospheric corrosion behaviors of three kinds of EH36 ocean platform steels with different compositions were investigated by cyclic wet-dry corrosion experiments. The results showed that the rust layer tended to be more compact by lowering C content and increasing Cr content. Protective corrosion products goethite (α-FeOOH) and lepidocrocite (γ-FeOOH) were the major constituents of the rust. The corrosion products can inhibit the increase of corrosion rates significantly during the later stage of corrosion.