During　construction　of　internal　prestressed　structure　with　geometrical　large　deformation,　Contact　friction　in　the　cable　and　structure　dissipates　a　considerable　amount　of　energy.　If　the　contact　problem　is　not　solved,　the　cable　force　will　not　be　defined.　Besides,　the　stress　in　forming　process　and　the　prestress　distribution　are　not　determined　accurately.　Shaped　process　of　the　prestressed　steel　truss　with　cable　in　bottom　chord　is　studied　in　this　paper　on　the　basis　of　finite　element　analysis.　Through　Comparison　between　theoretic　analysis　and　experimental　results,　the　cable　forces　calculated　with　contact　theory　and　the　inner　force　distribution　show　good　consistence　with　actual　forces　in　the　structure.　At　the　same　time,　the　paper　compared　the　force　distribution　calculated　with　contact　algorithm　and　temperature　algorithm　respectively　on　erection　procedure,　the　results　illustrated　that　there　maybe　existed　safety　problem　by　using　temperature　algorithm.　This　paper　not　only　provides　design　suggestions,　but　also　points　out　the　necessity　of　introducing　contact　algorithm.