The　cable　net　forming　the　minimum　surface　is　a　kind　of　equal　tension　cable　net,　and　any　cable　force　value　selected　will　not　change　the　configuration　of　the　minimum　surface.　The　cable　force　can　be　directly　set　as　the　constant　value　to　solve　the　minimum　surface.　The　cable　length　can　be　taken　as　the　only　iterative　solution　parameter　to　establish　the　equilibrium　equations　of　free　nodes,　solve　the　coordinates　of　free　nodes,　and　obtain　the　minimum　surface　configuration.　Base　on　this　theory,　a　form　finding　method　for　the　minimum　surface　of　cable　net,　namely　the　cable　length　iteration　method,　is　proposed　in　this　paper,　and　the　corresponding　analysis　steps　and　algorithm　flow　are　presented.　Some　typical　cases　with　different　boundary　conditions　and　topology　forms　were　used　to　compare　the　novel　method　with　the　traditional　force　density　method.　The　effectiveness　of　the　method　is　proved,　and　its　convergence　speed　and　calculation　accuracy　are　the　same　as　that　of　the　force　density　method.　For　the　configuration　of　the　cable　net　with　analytical　expression,　an　improved　method　for　the　cable　length　iteration　method　is　proposed,　and　the　results　show　that　the　improved　cable　length　iteration　method　can　solve　the　minimum　surface　configuration　faster　and　the　convergence　speed　can　be　doubled.