In　this　paper,　we　consider　the　2-catalog　segmentation　problem.　For　the　disjoint　version,　we　propose　an　approximation　algorithm　based　on　the　non-uniform　rotation　technique　using　a　semidefinite　programming　(SDP)　relaxation.　We　give　the　performance　curve　depending　on　the　ratio　between　the　value　of　optimal　SDP　solution　and　the　total　weight.　In　this　curve,　the　lowest　point　implies　the　approximation　ratio　is　0.7317　which　is　the　best　ratio　for　the　disjoint　version　until　now.　We　also　consider　the　performance　curve　of　the　joint　version.