The chemotaxonomy ofArachis has been studied with reference to the distribution pattern of different classes of secondary metabolites in general and free amino acids and phenolic constituents in particular. The chemical data are quantified to bring out the relative primitiveness/advancement of the taxa. It is found thatArachis apressipila, Arachis cardenasii andArachis hypogaea are primitive andArachis stenosperma is advanced. The chemical data are further expressed in the form of different synthetic numerical indices and depicted in polygons which point out to a fair amount of relationship among the taxa studied. From the dendrogram of cluster analysis it is evident that the genus could be divided into two infrageneric groups.