From  eight  years,  2012–2019,  of  field  research,  critical  work  in  herbariums  and  literature  reviews,  we  have established and identified as alien in the Yamal-Nenets Autonomous Area (YaNAA) a list of 216 vascular plant species from 144 genera and 35 families. The set of the ten richest families, by the number of species, alters in that the alien flora includes such families as Fabaceae, Polygonaceae and Chenopodiaceae, whereas the Cyperaceae, Salicaceae and Juncaceae families are absent from it. The richest by the number of species genus in the alien flora of the YaNAA is Chenopodium. We have classified the non-native species by the degree of naturalization, means of introduction and frequency of occurrence. We considered all alien species as kenophytes. For some arrival into the region can be traced back to 17th century, but most of them appeared at, or since, the end of 20th century or later. We distinguished three groups according to the naturalization degree: ephemerophytes (70%), kolonophytes (15%), and epekophytes (15%). Life history strategies and growth forms of the alien species differ from the native ones, with absolute dominance of herbaceous forms and a high proportion of annuals among them. By means of introduction, xenophytes prevail (82%), the remainder being number of ergasiophytes and xenoergasiophytes.