It　has　been　shown　that　as　concrete　strength　increases,　the　size　effect　becomes　more　pronounced　in　both　samples　and　members.　However,　the　effect　of　section　size　on　the　seismic　performance　of　high-strength　reinforced　concrete　columns　requires　further　confirmation.　For　this　purpose,　six　high-strength　reinforced　concrete　columns　were　subjected　to　monotonic　and　cyclic　loading　in　this　study.　The　experimental　results　indicate　that　the　relative　nominal　flexural　strength,　average　energy　dissipation　coefficient,　factor　of　safety,　and　local　factor　of　safety　all　exhibited　a　strong　size　effect　by　decreasing　as　the　column　size　increased.　Moreover,　the　size　effect　on　the　factor　of　safety　was　stronger　for　high-strength　columns　than　for　conventional　columns.　The　observed　changes　in　the　factor　of　safety　were　in　good　agreement　with　the　Type　2　size　effect　model　proposed　by　Bazant;　so,　using　the　local　factor　of　safety　and　Balant＇s　Type　2　model,　the　code　equation　for　moment　capacity　was　modified　to　provide　a　constant　factor　of　safety　regardless　of　column　size.