The electrochemical behavior of a carbon steel in 3% solution containing 10−2M of diamino‐1,2‐ethane has been investigated using a rotating disk electrode. Both steady‐state (current‐voltage curves for various disk rotation speeds) and transient (frequency analysis of the electrohydrodynamical and electrochemical impedances) measurements have been carried out. It was concluded that the oxygen reduction process at the corrosion potential was mainly controlled by charge transfer which is at variance with the uninhibited situation. Consequently, polarization resistance measurements can be used in this case to estimate corrosion rates. Regarding the mode of inhibition of diamino‐1,2‐ethane, the data are consistent with the chelation mechanism proposed for this type of bifunctional compound; it appears that the inhibitive action mainly affects the anodic reaction.