We report the occurrence data of 44 vascular plant taxa collected at various localities in Hungary (mainly the Danube–Tisza Interfluve and South Transdanubia) during floristic, vegetation and ecological field surveys between 2016 and 2018. Of the species in the present article, 27 are protected or strictly protected. In the paper we focused on plants that are rare regionally (e.g. Botrychium lunaria, Polystichum aculeatum) or in the whole country (e.g. Ophrys oestrifera, Ranunculus psilostachys), as well as on plants that occurred in unusual habitats (e.g. Corydalis solida). We also included new localities of weedy species, some of which (e.g. Opuntia humifusa, Sporobolus cryptandrus) may present nature conservation threats.