The coating of the reinforcement (primer) is a part of a complete system for concrete repair and, in fact, is frequently used. In spite of this, few studies have been devoted to study their efficiency to protect the reinforcement against further corrosion induced by chloride penetration.In these study five kinds of coatings, every one with a different protection mechanism, were applied on reinforcement steels and embedded in mortar with admixed chlorides and compared with a reference specimen. The technique used for monitor of corrosion intensity, Icorr, was the Polarization Resistance.The corrosion trends indicate very significative differences among the coating types after more than one year of testing. The results indicate that not all coatings are equivalent from the corrosion point of view.