The species diversity and safety of a 70-year-old collection of tree and shrub introduced species in the arboretum of the Dzhanybek Research Station, located in rainfed conditions of the semi-desert of the Northern Caspian region, was studied. The arboretum was created on hydromorphic meadow-chestnut soils in a mesodepression of relief in 1953. At the present stage, 75 species belonging to 23 families and 43 genera have been identified in the arboretum. It was analyzed that most of the species are represented by the family Rosaceae, the species of the families Caprifoliaceae, Elaeagnaceae, Fagaceae, Leguminosae, Oleaceae, Salicaceae, Sapindaceae, Ulmaceae are very numerous. Species with high ecological and biological potential have been identified. It is concluded that due to their own longevity, adaptive reactions, good self-renewal abilities, many species can exist for a long time and stably in semi-desert conditions. Species that can be recommended for creating sustainable socially significant plantations are proposed.