Abstract: In order to study the corrosion behavior of carbon steels and low alloy steels in seawater and to evaluate the anti-corrosion performance of the materials, 19 kinds of samples have been tested in seawater for 1, 8 and 16 years. Gumel approximate function of the extreme value statistical method is used to rectify the partial corrosion data. The corrosion performance of the 19 kinds of steels in seawater is comprehensively evaluated by the average corrosion data together with partial corrosion data.