Genista L. (Fabaceae) is distributed in Europe, South Africa, and West Asia and consists of almost 90 species in the world. Thirteen species of the genus are distributed in Turkey. Taxonomic problems of the species started to be resolved with recently developed DNA-based molecular methods. These methods, in contrast to phenotypical analyses, are free from the effects of environmental conditions. In this study, DNA of the species which belong to the Genista genus, grown naturally in Turkey and collected from the different localities, were isolated with a commercial kit. Inter-simple sequence repeat (ISSR) is a simple molecular marker system that provides reliable results. Based on ISSR data, genetic similarities and
dendrogram demonstrating the phylogenetic relationships among the Genista taxa were prepared by the NTSYSpc 2.0 software. In this study, infrageneric classifications of the Genista taxa belonging to the Flora of Turkey were conducted based on molecular data. ISSR analysis strongly supported the hypothesis that G. aucheri is accepted as the synonym of G. sessilifolia.