Damage　location　was　studied　based　on　single-layer　latticed　cylindrical　shell　experiment　model.　Finite　element　analysis　for　the　looseness　of　the　bolt-ball　was　done　by　FEA　software　ANSYS　using　neural　network　pattern　classification.　The　analysis　focused　on　the　whole　structure.　The　sub-structure　oriented　damage　location　method　was　used　in　order　to　verify　if　there＇s　damage　and　the　general　location　of　the　damage.　Then　the　node-location　oriented　technique　was　used　to　confirm　the　accurate　location　of　the　loosened　bolt-ball.　By　finite　element　analysis　and　experimental　results,　damage　identification　is　related　to　the　sensitivity　of　the　bolt-ball.　To　get　the　right　result,　the　sensitivity　should　be　more　than　2%.The　above　mentioned　method,　based　on　incomplete　modal　data,　can　be　used　for　the　location　of　loosened　bolt-ball.　The　above　mentioned　method,　based　on　incomplete　modal　data,　can　be　used　for　the　location　of　the　loose　of　the　bolt-ball.