One of the most aggressive environments for reinforced concrete (RC) is a marine environment such as that in the Persian Gulf region. In these conditions, reinforcement corrosion due to diffusion of chloride ions is the main deterioration mechanism. This paper presents the results of a study of a 30 year RC jetty structure in Bandar e-Imam Port, in the Persian Gulf region. Concrete durability factors were investigated using conventional and non-destructive tests to obtain the intensity of deterioration. The results showed extensive deterioration due to chloride-induced corrosion. It caused great deduction for service life in this structure. Although this structure was repaired in the past few years, poor repair work and materials caused intensity of corrosion damage rather than control of it.