This　paper　introduces　the　transformation　of　the　0-1　discrete　variables　into　continuous　variables　in　topological　optimization　problem　by　ICM　(Independence,　continuous　and　Mapping)　method.　The　first　step　is　to　convert　equivalently　the　discrete　problem　into　continuous　problem　taking　advantages　of　the　step-up　function;　The　second　step　is　to　define　the　polish　function　to　approach　the　step-up　function;　The　third　step　is　to　establish　the　mapping　model　by　introducing　the　filter　function　which　is　the　inverse　function　of　the　polish　function;　The　fourth　step　is　to　solve　the　model　with　continuous　variables　by　some　smooth　algorithms.　Some　representative　numerical　examples　of　continuous　structures　have　illustrated　the　process　of　transforming　the　topological　optimization　model　into　independent　level　one.　This　method　and　the　numerical　solutions　show　that　the　method　is　also　suitable　for　pure　mathematical　optimization　problems　with　0-1　discrete　variables.