Knowing　the　correct　corrosion　mechanism　of　Alloy　690　is　valuable　for　corrosion　protection　of　equipment.　Considering　the　semiconductor　characteristics　of　metal　oxide　film　on　the　corrosion　surface,　a　new　corrosion　dynamics　mechanism　was　proposed　based　on　the　quantum　mechanics.　At　first,　the　nature　and　characteristics　of　currents　were　analyzed　in　different　applied　potentials　by　the　band　structures　of　metal.　Then　the　relationship　between　corrosion　potential　and　current　was　developed　and　the　kinetic　mechanism　of　corrosion　was　explained　from　microscopic　view.　The　results　show　that　the　corrosion　process　is　controlled　by　four　kinds　of　electron　transfer　named　generation-compound,　diffusion,　tunneling　and　avalanche　in　the　interface　of　solution,　oxidation　film　and　metal.　It　is　reasonable　to　interpret　the　polarization　curve　of　Alloy　690　by　quantum　mechanics　because　this　relationship　has　very　good　consistency　with　that　of　experiments.　Key　words:　corrosion;　quantum　mechanics;　kinetic;　band　structures