The　connection　of　hollow　section　tubular　joints　is　crucial　for　structural　integrity,　and　the　mechanical　performance　of　high-strength　welding　joints　is　different　under　tension　and　compression.　This　paper　presents　an　investigation　into　the　connection　performance　of　grade　Q690　high　strength　steel　square　hollow　sections　(HSHS)　T　joints　under　axial　loading.　The　axial　tension　and　compression　tests　of　the　HSHS　T　joints　were　carried　out　and　comparative　analysis　of　failure　modes,　bearing　capacity　and　deformability　was　conducted.　Parameter　analysis　was　carried　out　based　on　the　validated　finite　element　model　and　a　wide　range　of　geometric　parameters　was　covered,　including　the　cross-sectional　width　ratio　and　the　wall　thickness　ratio　between　brace　and　chord,　and　the　width-thickness　ratio　of　the　chord.　It　is　shown　that　unlike　the　failure　of　the　chord　surface　and　the　side　wall　of　the　chord　under　compression,　the　bottom　surface　of　the　chord　will　also　be　damaged　under　tension,　and　the　deformation　and　bearing　capacity　of　grade　Q690　HSHS　T　joints　under　tension　are　higher　than　those　under　compression.　A　comparative　analysis　of　bearing　capacity　calculation　methods　provided　by　different　specifications　was　carried　out　and　the　rationality　of　the　material　reduction　factor　in　the　Eurocode　PR　EN　1993–1-8　was　compared　and　analyzed.　It　is　shown　that　the　calculation　results　of　the　tensile　bearing　capacity　have　a　lower　safety　level　compared　to　the　compressive　bearing　capacity,　and　considering　the　material　reduction　coefficient　can　help　improve　its　safety　due　to　its　discreteness.　©　2024　Institution　of　Structural　Engineers