To　study　the　influence　of　expansion　joint　parameters　on　vehicle-induced　dynamic　response　of　long-span　concrete-filled　steel　tube　(CFST)　arch　bridge,　this　paper　proposes　a　vehicle-bridge　coupling　dynamic　response　analysis　method　(vehicle-gap-bridge　coupling　dynamic　response　analysis　method)　considering　the　influence　of　expansion　joint　parameters.　Taking　a　long-span　half-through　CFST　arch　bridge　as　the　research　object,　the　influence　of　expansion　joint　height　difference,　support　stiffness,　and　joint　width　on　the　vehicle-gap-bridge　coupling　dynamic　response　was　investigated.　Results　show　that　under　the　design　parameters　of　expansion　joint,　the　vertical　impact　of　vehicle　on　expansion　joint　first　decreased　and　then　increased　with　the　increase　in　the　vehicle　speed,　and　the　vehicle-induced　impact　on　the　expansion　joint　was　more　significant　than　that　on　the　main　beam.　With　the　increase　in　the　vehicle　speed,　the　vehicle-induced　impact　coefficient　of　the　main　beam　showed　an　increasing　trend.　Considering　the　influence　of　expansion　joint　parameters,　the　vertical　impact　of　vehicle　on　the　main　beam　was　related　to　the　spatial　position,　and　the　impact　coefficient　of　the　main　beam　measurement　point　close　to　the　expansion　joint　position　was　greater.　Under　variable　expansion　joint　parameters,　the　rise　of　the　middle　cross　beam　led　to　the　increase　in　the　impact　of　the　vehicle　on　the　expansion　joint,　and　the　rise　or　fall　of　the　middle　cross　beam　could　both　cause　the　increase　in　the　impact　of　the　vehicle　on　the　beam　end,　resulting　in　the　increase　in　the　bearing　reaction.　When　the　support　stiffness　of　the　expansion　joint　decreased　or　the　width　of　the　joint　increased,　the　impact　of　the　vehicle　on　the　middle　cross　beam　of　the　expansion　joint　increased.　The　expansion　joint　parameters　had　little　effect　on　the　displacement　response　of　the　1/4　cross-section　and　1/2　cross-section　of　the　main　beam.　©　2022　Harbin　Institute　of　Technology.　All　rights　reserved.