Loop　cables　are　tensioned　to　prestress　in　the　construction　of　badminton　gymnasium　for　2008　Olympic　Games.　The　design　and　construction　of　the　cable-strut　joint　is　key　technique　to　assure　the　smooth　sliding　of　circumferential　cable　and　the　efficient　transfer　of　prestress　in　circumferential　cable.　This　paper　analyses　geometrical　construction　of　cable-strut　joint,　presents　method　for　calculating　the　prestress　loss　of　the　loop　cable.　The　nonlinear　contact　friction　finite　element　analysis　of　the　loop　cable　and　cable-strut　joint　is　carried　on　with　ANSYS,　the　prestress　loss　is　calculated　through　the　actual　construction　monitoring　data.　The　computed　results　are　comparied　with　the　actual　monitoring　data,　and　the　causes　for　larger　monitoring　pretress　loss　are　studied.　Following　suggestions　are　provided　for　cable-strut　joint　of　suspend-dome　that　loop　cables　are　tensioned　to　prestress　in　the　construction;　the　cable-strut　joint　cast　steel　should　be　made　precisely　to　satify　the　design　criterion;　the　constructional　detail　of　the　cable-strut　joint　should　be　improved　to　diminish　the　prestress　loss;　the　prestress　loss　value　of　cable-strut　joint　is　preferable　at　5%-6%,　meanwhile　the　cable-strut　joint　should　be　made　precisely　and　the　construction　should　be　controlled　strictly.