The　paper　focuses　on　the　dynamic　and　seismic　behavior　of　integral　abutment　steel　bridges　considering　nonlinear　soil-structure　interaction,　and　the　effects　of　design　parameters　of　the　integral　abutment　system　on　bridge　behavior.　3-D　finite　element　model　of　an　integral　abutment　steel　bridge　was　established　with　the　SAP2000　software,　and　nonlinear　link　elements　and　damper　elements　were　used　to　model　the　soil　reactions　behind　the　abutment　and　around　the　piles.　Modal　analysis　and　nonlinear　time-history　analysis　were　conducted,　with　corresponding　parametric　studies.　Results　indicate　that:　Compacting　the　backfill,　increasing　the　abutment　height-to-thickness　ratio,　and　increasing　the　foundation　stiffness　will　increase　the　dominant　longitudinal　frequency　of　the　bridge　structure,　while　H　pile　orientation　has　little　influence.　When　satisfying　the　design　requirements　and　in　a　reasonable　range,　compacting　the　backfill　behind　the　abutment,　increasing　the　abutment　height-to-thickness　ratio,　increasing　the　foundation　stiffness,　and　orienting　the　steel　H　pile　to　bend　about　its　strong　axis　can　effectively　reduce　the　pile-top　displacement,　as　well　as　seismic　response　of　girders,　abutments　and　piers,　but　increasing　the　foundation　stiffness　will　obviously　increase　pile-top　moment　at　the　same　time.　©　2018　Taylor　&　Francis　Group,　London.