This paper is aimed to study the corrosion resistance of iron which used in concrete layer in aqueous media (Rain water, Sea water, Tap water). Specimens was manufactured as cylinder by (10 x 3 mm) according to ASTM. Corrosion test was implemented by loss weight process in aqueous media (Rain water, Sea water, Tap water) for (1-30) day. Specimen was weighed before and after test. Corrosion rate
was calculated in all media and it was found that all media cases corrosion and corrosion was greater in sea water. Also potential state method was used to find the corrosion rate by using electrical cell the specimen represented the positive electrode. The negative electrode was made of platinum, a potential cell was limited by passing a current in the open circuit. The potential was compared with the potential of the
metal in the electrochemical chain. Then the circuit is closed and an electric current at this potential is passed with an increasing +100 volt , –100 volt, and finding the corrosion current through the intersection contacts to the cathodic and anodic electrode in accordance with Tafel's method and calculation the corrosion rate and
also the results of sea water corrosion is found higher than the other.