Abstract
The catholic protection have been applied to submerged part of marine steel structures. However, pitting corrosion was recognized on the steel surface under adhesive marine organisms even under Cathodic protection. It was not clear whether such pitting corrosion was occurred due to insufficient protective current or before the application of catholic protection. In order to clarify the reason, the site tests was carried out. From the test results, it was found that the catholic protection can stop the corrosion generated during of no protection. Also, it was found that adhesion of marine organisms on steel surface were harmless to protective effectiveness of catholic protection.
