Internal　stretch　forming　space　lattice　structure　(ISFSL)　is　theoretically　erected　through　finite　element　simulation　about　prestressing　force　on　cable　in　the　lower　tubular　member　of　ISFSL,　which　takes　both　geometrical　and　material　nonlinear　analysis　of　structure　into　consider.　And　the　forming　process　property　of　the　ISFSL　is　concluded　in　detail.　The　results　show　that　the　upper　chord　of　ISFSL　is　the　primary　bearing　member,　which　presents　large　bending　deformation,　be　mainly　subjected　to　bending　moment,　and　the　axial　stress　is　very　little.　Rigid　arm　stress　and　strain　is　much　small,　which　provides　some　restraint　to　the　ISFSL,　in　addition　its　rotary　movement　is　large.　The　stress　result　from　the　erection　of　ISFSL　of　the　others　is　very　small.