The corrosion behavior of electroplastic rolled (ER) AZ31 magnesium alloys subjected to high energy electric pulse treating (EPT) and conventional heat treating (CHT) respectively in 3.5%NaCl solution (mass fraction) were investigated using potentiodynamic polarization curves, electrochemical impedance spectroscopy (EIS), corrosion morphology observation and corrosion rate measurement. The results indicate that the corrosion resistance of the as-ER alloys is enhanced by EPT or CHT, which is attributed to complete recrystallization and lower dislocation density after treatments. Compared with CHT, the EPT process can increase mechanical properties of materials more significantly, but it is not good at the corrosion resistance improvement, which may result from more corrosion micro-cells caused by finer grains.