Socket　connection　is　commonly　used　for　connections　between　precast　components,　which　has　the　advantages　of　good　integrity　and　high　construction　fault　tolerance.　To　further　investigate　the　bond　-slip　behavior　and　improve　the　engineering　design　of　Ultra　High　-Performance　Concrete　(UHPC)-filled　concrete　-filled　steel　tube　(CFST)　column　-beam　socket　connections,　this　paper　conducted　bond　-slip　experiments　on　UHPC-filled　CFST　socket　connections　(UCSC)　with　different　parameters　(socket　depth,　presence　of　studs)　to　reveal　their　bond　-slip　properties.　In　addition,　to　conduct　further　parametric　analysis,　a　reliable　finite　element　model　(FEM)　of　the　UCSC　joint　was　developed.　Based　on　the　experimental　data　and　finite　element　analysis　(FEA)　results,　a　simplified　calculation　equation　and　a　normalized　bond　-slip　relationship　model　was　established　to　estimate　the　bond　-slip　performance　of　UCSC.　The　research　results　suggested　that　the　bond　-slip　behavior　of　the　UCSC　was　sensitive　to　the　socket　depth,　the　presence　of　studs　and　the　diameter　of　CFST.　The　FEM　is　capable　of　estimating　the　forcedisplacement　relationship　and　the　damage　distribution　of　the　UCSC　joint　under　vertical　loads.　The　developed　simplified　equation　and　normalized　bond　-slip　relationship　have　been　validated,　and　can　be　employed　to　predict　the　ultimate　bonding　bearing　capacity　and　the　bond　-slip　relation　of　UCSC　joints,　respectively.　Finally,　design　recommendations　were　proposed　for　the　engineering　design　of　UCSC.　The　UCSC　method　is　required　to　ensure　a　socket　depth　at　least　1.0　D　and　a　certain　number　of　shear　studs　to　connect　the　column　-beam　joint.