Abstract: The corrosion behavior of X80 pipeline steel in red soil with different water content were studied by electrochemical testing, including open circuit potential, potentiodynamic polarization curves and electrochemical impedance spectroscopy. The results showed that the free corrosion potential, corrosion rate and corrosion type of X80 pipeline steel were closely related to the water content of red soil and the thin liquid film adsorbed on the surface of X80 pipeline steel. With the increase of water content of red soil, the continuity of adsorbed liquid film on the surface of X80 pipeline steel increased, the open circuit potential decreased and the corrosion current density increased. With the increase of water content of red soil, the corrosion mode of X80 pipeline steel changed from localized corrosion to uniform corrosion.