The　article　focuses　on　the　dynamic　identification　and　finite　element　(FE)　modelling　of　a　butterfly-arch　stress-ribbon　pedestrian　bridge　in　Fuzhou,　Fujian,　China.　The　Stochastic　Subspace　Identification　method　yields　an　estimate　of　the　operational　modal　parameters.　A　highly　synchronous　tri-axial　wireless　sensor　network　was　deployed　on　the　bridge　deck　to　record　the　structure＇s　ambient　vibration.　Eight　stable　modes　in　the　frequency　range　3.59-14.92　Hz　were　found,　associated　with　prevalent　bending　and　torsional　deformations.　Four　distinct　FE　models　of　the　bridge　with　progressive　complexity　and　accuracy　were　developed　to　investigate　the　sensitivity　of　the　modal　features　to　the　modelling　choices.　The　FE　model　characterised　by　the　fittest　agreement　with　the　experimental　modal　parameters　was　used　for　the　automatic　parametric　optimisation　based　on　a　sensitivity-based　algorithm.　The　stiffness　of　the　springs　simulating　the　soil-structure　interaction,　the　elastic　modulus　of　the　concrete　deck　and　the　elastic　modulus　of　the　tendons　were　chosen　as　updating　parameters　for　a　total　of　eight　parameters.　The　effect　of　non-structural　elements　(handrails)　and　prestress　on　the　modal　features　are　also　investigated.　The　final　advanced　FE　model　developed　can　serve　as　baseline　for　a　long-term　monitoring　of　the　bridge　during　its　life-cycle,　and　also　provides　some　recommendations　to　practitioners　and　scholars　all　over　the　world　for　the　modelling　and　analysis　of　this　particular　kind　of　footbridges.