Abstract:This paper is a continuation of the previous one which has been dealing with a numerical taxonomic study on the variation patterns on popula-tion level of 5 species of Mosia (Labiatae) in the same region.In the prev-ious paper, we have come to the conclusion that the 5 species of Mosia had differentiated into two main phylads in its early stage of evolution. In the present study, the essential oil extracted from the same species was analysed by means of a gas chromatograph-mass spectral in order to reveal the phylogenetic relationships of the said species on chemical level.