Precast　reinforced　concrete　(RC)　bridge　columns　are　critical　substructure　components　for　Accelerated　Bridge　Construction　(ABC),　which　attracts　significant　attention　all　over　the　world　in　recent　decades.　However,　seismic　behavior　of　precast　RC　bridge　columns　in　corrosive　environment　and　related　retrofit　methods　are　rarely　studied.　To　fill　out　this　knowledge　gap,　in　this　study,　four,　1/4-scaled　precast　RC　bridge　columns　of　various　corrosion　levels　were　designed,　constructed　and　tested　in　a　pseudo-static　manner　to　gain　in-depth　understanding　of　corrosion　on　the　seismic　behavior　of　this　type　of　columns.　Two　of　these　columns　with　higher　corrosion　levels　were　retrofitted　with　carbon　fiber　reinforced　polymer　(CFRP)　fabrics　in　the　plastic　hinge　zone　to　assess　the　effectiveness　of　this　retrofit　measure.　Corrosion　levels　of　the　specimens　were　obtained　through　an　electrochemical　method　to　accelerate　the　corrosion　process　at　the　plastic　region.　It　was　found　that　corrosion　in　the　reinforcement　was　uneven　across　the　section　and　was　much　severer　at　the　joint　of　precast　bridge　columns.　It　was　also　found　that　even　the　low　corrosion　level　of　longitudinal　reinforcement　(i.e.　7.2%)　can　result　in　a　significant　decrease　(i.e.　＞15%)　in　the　lateral　load　capacity,　energy　dissipation,　ductility　and　ultimate　displacement.　Hence,　the　retrofit　of　corroded　precast　RC　bridge　columns　should　be　performed　at　low-level　of　corrosion.　The　test　results　also　indicate　that　corrosion　has　more　adverse　effect　on　the　ultimate　displacement　and　ductility　than　the　strength.　In　addition,　retrofitting　bridge　columns　of　higher　corrosion　levels　(i.e.,　＞10%)　using　CFRP　jackets　could　effectively　protect　the　columns　from　damage　in　the　plastic　hinge　zones.　However,　the　damage　pattern　was　shifted　to　fracture　of　the　longitudinal　rebars　at　the　column-footing　interface,　resulting　in　substantial　reduction　in　the　ultimate　displacement　capacity.　Therefore,　it　is　not　recommended　to　retrofit　precast　RC　bridge　columns　of　high　corrosion　level　using　CFRP　jackets　alone.