A　baseline　finite　element　model　is　a　reference　in　structural　damage　detection　and　long-term　health　monitoring.　An　ambient　vibration　measurement　based　procedure　is　presented　to　develop　such　a　baseline　model　for　a　newly　constructed　Qingzhou　cable-stayed　bridge　over　the　Ming　River,　Fuzhou,　China.　A　605　in　main　span　of　the　bridge　is　currently　the　longest　in　the　world　among　all　completed　composite-deck　cable-stayed　bridges.　The　procedure　includes　several　tasks:　finite　element　modeling,　field　ambient　vibration　testing,　parametric　studies　and　model　validation.　It　is　demonstrated　that　the　ambient　vibration　measurements　are　enough　to　identify　the　most　significant　modes　of　large　span　cable-stayed　bridges　with　a　low　range　(0-1.0　Hz)　of　natural　frequencies　of　interest.　Some　important　issues　in　the　modeling　of　such　a　complicated　bridge,　such　as　the　initial　equilibrium　configuration　due　to　dead　load,　geometrical　nonlinearities,　concrete　slab,　the　shear　connection　of　the　composite　deck,　and　the　longitudinal　restraints　of　the　end　expansion　joints,　have　been　clarified.　The　developed　three-dimensional　finite　element　model　of　the　bridge　has　achieved　a　good　correlation　with　the　measured　natural　frequencies　and　mode　shapes　identified　from　field　ambient　vibration　tests.　(c)　2004　Elsevier　Ltd.　All　rights　reserved.