Data are reported on 23 vascular plant species new for Karelia, which were mainly recorded from urban and rural settlements of the republic. Detailed information about the finding circumstances is provided for each of the species, and for many of the species the reasoning for classifying as native or non-native is also given. The recently described species of the lady’s mantle genus Alchemilla mininzonii Czkalov, Alchemilla tichomirovii Czkalov and Alchemilla vorotnikovii Czkalov, as well as Lemna turionifera Landolt and Typha incana Kapitonova & Dyukina are most likely native species. 18 species: Thuja occidentalis L., Corydalis bracteata Pers., Cannabis ruderalis Janisсh., Viola odorata L., Alcea rosea L., Alchemilla glyphodonta Juz., Alchemilla schistophylla Juz., Alchemilla stellaris Juz., Alchemilla substrigosa Juz., Persica vulgaris Mill., Pyrus communis L., Foeniculum vulgare Mill., Galium tricornutum Dandy, Cymbalaria muralis G. Gaertn., B. Mey. & Scherb., Ornithogalum angustifolium Boreau, Allium fistulosum L., Allium subgen. melanocrommyum (Webb & Berth.) Rouy, Erythronium sibiricum (Fisch. & C. A. Mey.) Krylov are believed to be adventitious.