The motivation for the work was to investigate the possibility of using low alloyed steel as the construction material in the adsorber in a CO2 separation plant for flue gas from a gas fired power plant. In this work the corrosion rate of ST 52 (ASTM A572 ) steel in monoethanolamine (MEA) solution was studied. The corrosion testing was mainly performed on a rotating disc electrode and electrochemical impedance was used to estimate the corrosion rate. The parameters studied were rotation rate influence of oxygen and degradation of the MEA. The results shows a significant increase in the corrosion rate when oxygen was introduced to the system especially when the rotation rate was high. The corrosion also increased when the MEA solution was degraded.