A　simple　bilinear　stress-strain　model　of　fiber-reinforced　polymer　(FRP)　confined　concrete　was　used　to　analyze　the　approximate　cross-sectional　ductility　of　undamaged　circular　columns　strengthened　with　hybrid　FRP　under　seismic　loads.　The　effect　of　reinforcement　corrosion　on　the　sectional　ductility　was　considered　by　the　loss　of　rebar　cross-sectional　area,　the　reduction　of　rebar＇s　mechanical　properties　and　the　degradation　of　interface　bonding　between　rebar　and　concrete.　Then,　a　simple　analytical　model　was　established　to　estimate　the　ductility　of　potential　plastic　hinge　regions.　Finally,　a　non-iterative　displacement-based　seismic　design　program　for　reinforced　concrete　corroded　columns　strengthened　with　hybrid　FRP　was　presented　on　the　basis　of　the　simple　analytical　model.