Abstract��The corrosion resistance of X80 pipeline steel was investigated in simulated solution of saline-alkali soil using weight loss method, electrochemical measurement, scanning electron microscopy (SEM) and x-ray diffraction (XRD). The results show the average corrosion rate of X80 steel decreased obviously, and corrosion tendency increases��this is induced by change of corrosion morphology from uniform corrosion to pitting corrosion. The cathodic progress is dominated by oxygen activation control. The corrosion product is basically FeOOH (surface layer) and Fe3O4 (inner layer). The corrosion resistance and corrosion morphology of X80 steel samples is dependent on the integrality and compactness of corrosion product films. The content of Cl- dominated the corrosion severity.