The　influence　of　a　direct　current　(DC)　stray　current　on　the　corrosion　and　cathodic　disbondment　of　X80　steel　coated　with　a　polyethylene　(3PE)　coating　in　3.5%　NaCl　solution　was　studied　by　immersion　experiments,　electrochemical　tests,　three-dimensional　microscopy,　and　a　surface　analysis.　The　results　showed　that　the　potential　of　the　X80　steel　sample　shifts　under　the　direct　current.　After　100A/m(2)　DC　interference　was　applied,　the　potential　of　the　sample　in　the　anode　region　positively　shifted　from　-0.68　to　-0.43　V.　At　the　same　time,　the　sample　in　the　cathode　region　negatively　shifted　to　-1.45　V.　Under　the　DC　anode　action,　the　X80　steel　corrosion　exhibited　no　passivation　and　followed　Faraday＇s　law　of　electrolysis,　in　which　the　corrosion　rate　is　proportional　to　the　current　density.　Three-dimensional　(3D)　digital　microscopy　showed　that,　as　the　DC　current　increased,　the　depth　of　the　corrosion　pit　also　increased　(gradually),　indicating　a　higher　corrosion　degree.　The　sample　in　the　cathode　region　only　underwent　a　hydrogen　evolution　reaction,　which　caused　cathodic　disbondment　of　the　coating.　The　stray　current　had　a　critical　current　density　for　the　coating　disbonding:　the　coating　delamination　area　reached　its　maximum　and　then　remained　unchanged.