The effects of operating parameters on the corrosion of carbon steel in the monoethanolamine (MEA)-H2O-CO2-O-2-SO2 System were investigated using two different corrosion measurement techniques. The corrosion studies were conducted using a 273A potentiostat using MEA, O-2, and SO2 concentrations and CO2 loading ill the ranges of 1-7 kmol/m(3), 0-100%, 0-204 ppm, and 0-0.5 mol CO2/mol MEA, respectively, at corrosion temperatures in the range of 303-353 K. The experimental results showed, for the first time, that a higher concentration of SO2 ill a simulated flue gas stream induces a higher corrosion rate essentially because of the increase in the hydrogen ion concentration generated by reactions of SO2 and H2O as well as SO2, O-2, and H2O. Also, an increase in oxygen concentration in the simulated flue gas stream causes a higher corrosion rate due to the increasing solubility of oxygen and, in turn, a higher amount of dissolved oxygen in the liquid phase. The results further show that an increase in the concentrations of MEA, O-2, and SO2 as well as CO2 loading will cause the generation of higher amounts of hydrogen or hydronium ions, as well as carbonic acid and bicarbonate ions, and this is what leads to a higher corrosion rate.