In view of diversified morphology among those Classes in Molluska, the phylogenetic relationship among them is still unclear so far. Although there is a possible phylogeny among the various taxa of mollusks according to the similarities and differences in morphological level, the phylogenetic relationship is yet relative rough, in that it can not be supported by 18S rRNA. Therefore, This paper only focuses on the relationship between Gastropoda and Cephalopoda with hemocyanin in hierarchical levels and get some interesting results.