Despite many advantages of ductile iron pipelines, they are susceptible to corrosion and must be protected against it. Customary protection solution is to apply sacrificial metal coatings such as zinc and aluminum and arc spraying, as one of thermal spray methods, has been vastly used for such coatings in recent years. In this research, coatings made up of pure zinc, Aluminum, individual layers of them and co-spray of zinc-aluminum were applied on ductile cast iron substrate through arc-spray process. In order to investigate the effect of coating thickness on corrosion protection and mechanical performance, samples were prepared in two approximate thicknesses; 50 and 100 µm. Scanning electron micrographs of coatings cross sections revealed crack-free coatings with intimate contact with the substrate and low oxide content. For evaluation of coating adhesion to cast iron substrate, bending tests were carried out on typical samples; the co-sprayed sample of 50µm and the double layer coating showed the best and lowest performance, respectively. The co-sprayed samples had the ability of bending up to 28 degrees. Results of micro-hardness testing indicated that the maximum and minimum values of hardness belong to aluminum coating and zinc coating of 100µm thickness, respectively. With thickness increase in aluminum, the hardness rose and in zinc coatings decreased. In the case of co-sprayed samples, the increase in thickness, did not have significant change in hardness values. In order to evaluate the corrosion behavior of samples with and without coating, potentiodynamic cyclic polarization test in 3.5% (wt) NaCl and salt mist tests were employed. The results indicated higher rate of corrosion of aluminium and zinc coatings compared with their bulk metal, due to penetration of corrosive solution through surface porosities to the interface and formation of galvanic cell. Zinc coated samples and its uniform corrosion trend resulted in proper sacrificial corrosion performance. On the other hand, aluminium, by aggregation of corrosion products in porosities and confining entrance of corrosion agents to coating, protected the substrate. But by progression of test, pitting corrosion had occurred on its surface. The corrosion behavior of double layer samples was similar to aluminium but in its pitting corrosion sites, zinc acted its sacrificial performance and protected the substrate against corrosion. Thus, double layer sample had lowest corrosion current density. The results of salt spray test during 750 hours showed that after 70 hours, the surface of ductile iron sample, was completely corroded. But no signs of red rust was noticed in all test long on the surface of coated samples. Corrosion signs were observed at the corners of aluminium coated samples after 500 hours. The corrosion trend of double layer coated sample was similar to aluminum without signs of corrosion at corners. Co-sprayed samples corrosion trend was just darkening the surface of sample and had better performance. Keywords: Ductile cast iron, Thermal spraying, Corrosion behavior, Zinc coating, Aluminium coating.