Nowadays,　the　events　of　bacterial　infection,　food　poisoning　and　biological　corrosion　damage　are　increasingly　arising.　It　is　urgent　to　develop　new　antibacterial　material　to　fight　against　the　drug-resistant　bacteria.　In　this　work,　Ag-bearing　antibacterial　duplex　stainless　steels　were　prepared　by　adding　Ag　or　Cu-Ag　alloy　particles.　The　microstructure　and　distribution　of　Ag-rich　phases　and　Ag　electrovalence　of　the　materials　after　solution　treatment　at　different　temperatures　have　been　discussed　in　detail　by　ESEM,　XRD　and　TEM.　The　antibacterial　effects　of　the　materials　were　tested　by　film-cover　method,　and　compared　with　CD4MCu　and　Cu-bearing　antibacterial　duplex　stainless　steel.　The　results　indicated　that　some　Ag-bearing　phases　in　diameter　of　about　8　μm　in　the　matrix　of　the　material　prepared　by　adding　Ag　after　the　solution　treatment　at　1050　and　1150　were　observed,　and　increasing　temperature　could　not　improve　the　solution　solubility　of　Ag-bearing　phases.　In　addition,　some　Ag-bearing　phases　in　diameter　of　45　nm　was　found　in　the　matrix　of　the　material　after　solution　treatment　at　1150.　For　the　material　prepared　by　adding　Cu-Ag　alloy　particles　after　solution　treatment　at　1050　and　1150,　the　solubility　of　Ag-bearing　phases　increased　with　the　solution　temperature　rising.　And　the　smaller　the　Cu-Ag　particles　were,　the　easier　the　Ag-bearing　phases　dissolved.　For　the　material　prepared　by　adding　Cu-Ag　alloy　particles　in　diameter　of　150~300　mm　after　the　solution　treatment　at　1150,　Ag-bearing　particles　were　completely　dissolved　into　γ　phase　while　some　in　diameter　of　about　18　nm　were　evenly　distributed　in　α　phase.　Antibacterial　tests　showed　that　Ag-bearing　antibacterial　duplex　stainless　steels　prepared　by　adding　different　sizes　of　Cu-Ag　alloy　particles　exhibitted　excellent　antibacterial　effect.　The　material　prepared　by　adding　Ag　granules　had　the　antibacterial　effect.　©　Copyright.