The　structure　and　constructional　sequence　of　the　abutment　of　integral　abutment　bridges　are　brought　out.　On　the　basis　of　Shangban　Bridge,　the　inner　force　and　the　stress　of　the　abutment　node,　and　the　cracks　of　the　stabs　are　analyzed　under　the　act　by　several　load　cases　through　building　the　dimensional　beam　model　and　solid　model.　The　concept　of　the　relative　stiffness　is　brought　out,　and　the　effect　of　the　pile　relative　stiffness　and　the　abutment　height　on　the　loaded　property　of　the　abutment　node　has　been　discussed.　The　researching　results　will　promote　to　design　integral　abutment　bridges　in　the　engineering.