The　structural　characteristics　in　every　construction　stage　of　cable　dome　were　analyzed.　Adopting　the　theory　of　nonlinear　time-varying　mechanics,　the　variations　of　internal　force　and　displacements　were　obtained.　Numerical　results　indicated　that　maximum　internal　force　in　construction　process　was　greater　47%　than　that　in　designed　state,　the　paper　reached　a　conclusion　that　it　was　not　safe　to　design　if　the　time　varying　effect　was　not　considered　in　the　construction　process　analysis.　At　last,　advices　on　design　and　construction　of　cable　dome　were　made.