Viticulture production and winemaking of Montenegro are mostly based on growing of autochthonous grapevine varieties. Besides Vranac variety, Kratosija variety takes a significant place in Montenegrin autochthonous grapevine varieties. According to many literature data, Kratosija is an autochthonous grapevine variety whose origin and cultivation started earlier than with Vranac variety. Because of its heterogeneity, it is not so much represented in Montenegrin vineyards and it is mostly found in combination with Vranac variety. The research results about the origin of Vranac variety are shown in this paper. Furthermore, genetic identification which approved originality of Vranac variety is shown and it has also been approved that autochthonous variety Kratosija has the same genetic profile as cv. Zinfandel. The paper presents multi-annual results of examination of variability of their populations and work on clonal selection. Mother vines were selected and vineyards of pre-base and base category of Vranac variety potential clones were planted. The results achieved, in view of manifesting agro-biological, economic and technological characteristics, point to the need for further work on clonal selecton of these grapevine varieties.