In　the　paper　both　a　direct　method　and　a　sensitivity-based　iterative　method　have　been　applied　to　update　a　finite　element　model　of　a　curved　cable-stayed　bridge.　The　direct　method　is　known　as　the　Douglas-Reid　algorithm.　The　sensitivity-based　method　is　a　Trust-Region　algorithm.　Thirteen　experimental　modes　identified　between　0　and　10　Hz　under　ambient　condition　have　been　considered　as　reference　modal　data.　An　a-priori　finite　element　model　has　been　implemented　by　using　the　SAP2000　software.　The　model　has　been　firstly　manually　tuned　and　then　updated　through　computational　procedures　implemented　in　MATLAB.　The　results　of　the　direct　and　the　iterative　methods　have　been　compared　to　each　other　for　the　specific　case　study.