To provide a corrosion preventive method for a steel structure which prevents the intrusion of sea water through a small gap developed over time between concrete and a steel material caused by steel projections or the like embedded partially in a concrete wave-breaking plate to which electrolytic protection is not applied, thereby eliminating corrosion at the ground-buried position.

In the corrosion preventive steel structure partially embedded in concrete, a zinc rich coating film layer is formed around the outer circumference of the steel structure, en epoxy resin covering layer is formed on the zinc rich coating film layer, and furthermore, a water swelling rubber layer is formed in a head-band state on the epoxy resin covering layer below the concrete-buried position.