Abstract: Numerical taxonomic studies were performed on 57 populations of 15 Stipa species belonging to 5 different sections, concerning intra-population and inter-populations variations as well as inter-specific relationships. The most variable morphological characters useful in the species delimitation were also determined. The species studied also differed significantly in most of the quantitative characters studied and the mean of such characters may be of use in the species delimitation. The clustering showed distinctness of the species studied as the populations of each species are placed close to each other and separate from the other species.