The paper presents new records for 18 vascular plant species from six Eurasian countries. Three taxa (Lepidium densiflorum, Stipa czerepanovii, Xanthium albinum) are reported from Kazakhstan, one (Ranunculus schmakovii) from Mongolia, three (Dianthus campestris, Ranunculus kauffmannii, Viola suavis) from Poland, five (Eragrostis amurensis, Linum catharticum, Ludwigia peploides subsp. stipulacea, Pyrethrum mikeschinii, Solidago canadensis) from Tajikistan, five (Clinopodium menthifolium, Juncus effusus, Mollugo cerviana, Poa sphondylodes, Vulpia myuros) from Russia, and one (Orobanche alba subsp. xanthostigma) from Georgia. Ten of the taxa presented (Clinopodium menthifolium, Dianthus campestris, Eragrostis amurensis, Juncus effusus, Lepidium densiflorum, Mollugo cerviana, Solidago canadensis, Viola suavis, Vulpia myuros and Xanthium albinum) are regarded as alien to the studied areas, whereas the remaining eight are native elements to the flora of the countries. For each species, synonyms, general distribution, habitat preferences, taxonomy with remarks on recognition and differentiation of the species from the most similar occurring in a given country, as well as a list of localities recorded (often far from the previously known areas), are presented.