To　obtain　the　concept　design　of　the　truck　frame　structure,　the　efficient　computer　aided　design　method　to　optimize　the　structure　of　the　truck　frame　is　provided　based　on　independent　continuous　mapping　method.　And　the　transformation　of　the　local　stress　constraints　of　element　into　the　global　stain　energy　constraints　of　structure　is　achieved　by　virtue　of　the　strategy　of　globalization　of　stress　constraints.　The　optimal　topology　model　of　the　truck　frame　structure　subjected　to　the　structural　weight　is　established　with　stress　constraints.　The　problem　about　topological　optimization　of　continuum　structure　with　multi　degree　freedom　under　stress　constraints　is　studied.　In　addition,　the　dual　model　corresponding　to　the　optimal　model　of　continuum　structure　is　solved　by　the　serial　quadratic　programming.　Furthermore,　the　numerical　analysis　about　the　truck　frame　structure　shows　that　the　method　is　effective　and　efficient.