To　prevent　the　numerical　instabilities　about　checkerboards,　mesh-dependency　and　gray-scale　elements　in　structural　topology　optimization　with　strain　energy　constraints,　an　improved　ICM　method　based　on　the　bi-directional　filter　function　is　presented.　The　sequential　quadratic　approximate　algorithm　is　applied　to　solve　the　optimal　model　for　continuum　structure　established　in　this　paper.　A　classical　numerical　example　is　discussed　which　shows　that　the　present　method　is　effective　and　efficient.