Antibacterial　copper-rich　phases　such　as　?-Cu　were　precipitated　in　copper-bearing　antibacterial　duplex　stainless　steels　after　antibacterial　treatment.　In　this　paper,　the　effects　of　antibacterial　treatment　on　the　corrosion　resistance　properties　of　copper-bearing　antibacterial　duplex　stainless　steels　were　investigated　by　electrochemical　methods.　The　film-cover　method　was　used　to　antibacterial　tests.The　results　showed　that　as　the　antibacterial　treatment　temperature　increased　in　the　rang　of　540∼580°C,　the　copper　-rich　precipitates　grew　faster　and　evolved　from　granular　into　rod-like.　With　the　proportion　of　rod-like　copper-rich　phases　in　matrix　increased,　the　resistant　to　pitting　corrosion　decreased　and　the　positions　of　copper-rich　phase　precipitated　were　apt　to　become　pitting　nucleation　source.The　presence　of　?-Cu　and　other　copper-rich　phases　in　passive　film　reduced　the　overall　potential　and　passive　film　resistance,　decreasing　the　stability　of　passive　film.　Antibacterial　test　showed　that　with　the　treatment　temperature　increased,　the　volume　fraction　and　the　uniformity　of　the　distribution　of　copper-rich　precipitates　in　the　matrix　first　increased,　then　decreased,　resulting　in　the　changes　in　antibacterial　properties　of　the　steels,　and　560　°C　obtained　the　best　antibacterial　effect.　©　(2012)　Trans　Tech　Publications,　Switzerland.