Abstract: The corrosion behaviors of X80 steel welded joint in soil solution, rain water and snow water in Fushun area were investigated by the potentiodynamic polarization and electrochemical impedance spectroscopy, and then the corrosion morphology was observed by optical microscope. The results show that the polarization curves of the base material sample and weld sample from X80 steel welded joint exhibited typical active dissolution characteristics in the three corrosive solutions. The polarization resistance and diffusion index of the samples increased in soil solution, rain water and snow water in turn, indicating the decrease of corrosion rate and the increase of surface film density in turn. The corrosion resistance of the X80 steel welded joint in the three corrosive solutions decreased in the order of snow water, rain water and soil solution. In the same corrosive solution, the corrosion resistance of the weld sample was better than that of the base material sample.