Abstract <p>Understanding the impacts of alien species on nature and man is crucial to setting priorities for managing invasions, and classification by impact type and ranking of species on this basis is a prerequisite for such decisions. The impact on native species, natural communities, and human life was assessed for 147 invasive alien plant species of European Russia using the Generic Impact Scoring System (GISS). The GISS protocol includes both ecological and socioeconomic criteria and is based on published data (in this study, 689 publications were used for scoring), taking into account the maximum impact in the secondary range. Among all the indicators, the impact on agriculture (crop production) prevails, while among the ecological indicators, the highest scores are for the impact on ecosystems and indirect impact on different biotic groups, including competition. An measure of species invasiveness is proposed taking into account the spread of the species as invasive in the regions of European Russia. Ranking of species by the indicators obtained revealed a relatively good correspondence with the list of species recommended by experts as the most dangerous alien species in Russia, but the choice of priorities among them is difficult without an objective impact assessment. In general, the use of standardized impact scoring schemes and a transparent procedure for determination of the impact status of alien species provide a more reliable approach to setting priorities in management and assessing the risks of invasions than expert opinion alone. A list of species has been suggested for which legislative and practical measures in order to limit their distribution are necessary first of all.</p>