Based　on　the　ICM　(Independent　Continuous　Mapping)　method,　different　filter　functions　for　element　weight,　element　allowable　stress　and　element　stiffness　are　introduced　to　change　the　0-1　type　discrete　topological　variables　to　continuous　topological　variables　between　0　and　1,　so　a　topological　optimization　model　with　continuous　topological　variables　is　built.　The　stress　constraints　are　transformed　into　movable　lower　limits　of　topological　variables　with　the　full　stress　criterion　and　the　displacement　constraints　are　transformed　into　explicit　expressions　with　the　unit　virtual　load　method,　thus　the　topological　optimization　model　is　explicit.　To　improve　the　solving　efficiency,　the　dual　model　of　the　original　optimization　model　is　solved　according　to　the　dual　theory　by　iteratively　solving　the　dual　model　in　its　dual　space.　Three　criteria　which　are　no　singular　structure,　no　violated　constraints　of　structural　responses　and　no　changed　structural　weight　are　introduced　to　judge　iteration　convergence.　According　to　the　three　criteria,　an　appropriate　doorsill　is　found　by　self-adaptively　adjusting　a　discount　factor,　and　then　the　continuous　topological　variables　can　be　regressed　to　the　0-1　type　discrete　topological　variables.　With　the　opening　of　MSC/Nastran　and　the　PCL　(Patran　Command　Language)　environment　of　MSC/Patran,　the　topological　optimization　program　of　frame　structures　with　multiple　variables　is　implemented,　which　can　satisfy　the　stiffness　and　strength　constraints.　Numerical　results　show　that　it　is　speedy　and　efficient　to　solve　the　topological　optimization　problem　of　frame　structures　with　ICM　method.