Аннотация:In North Ossetia populations of Greek Clouded Yellow which features and differences from other known populations were not studied so far were revealed. The purpose of this study was to learn the features of North Ossetia populations and their differences from the known populations in other parts of the area. It was used the reference practical standard of entomological material’s collecting - catching by air entomological net and registration – writing of field labels; of visual observations: route inspections, expeditions, maintaining the field diary and images taken with cameras. Geographical coordinates and absolute heights were measured by means of the Garmin etrex 20x GPS navigator. Determination of butterflies was carried out on external diagnostic signs the method of the comparative analysis was applied. It is established that North Ossetia populations of Greek Clouded Yellow differ from other North Caucasian populations in existence of yellow coloring females. This fact together with geographical isolation from other Caucasian populations of the species has confirmed the assumption that butterflies from North Ossetia fall into to special subspecies. Studying of one species features in various populations inhabiting different parts of the area is very important for the best knowledge of biological diversity.