In this paper, we report our floristic observations collected from gravel pits in the Sajó–Hernád Plain (Borsod-Abaúj-Zemplén county, Northeast Hungary). We present a total of 101 occurrence data from 13 pits, belonging to 45 vascular plant species and one hybrid. Most of the observations come from abandoned mines, but we also describe occurrences from actively mined areas. Ten of the presented species are new to the flora of the micro-region (Cyperus flavescens, Dysphania botrys, Helminthotheca echioides, Hippophae rhamnoides, Panicum dichotomiflorum, Ranunculus circinatus, Solanum lycopersicum, Spergularia rubra, Thymelaea passerina, Zannichellia palustris). Some of the species listed in the enumeration are taxa for which data are scarce even at the national level (e.g., Bolboschoenus laticarpus, B. planiculmis, Utricularia ×neglecta). We report some recent occurrences of invasive alien species (Erechtites hieraciifolia, Symphyotrichum ciliatum, S. novi-belgii), we provide data on common or sporadic aquatic plant species for which available data are scarce (Ceratophyllum demersum, Myriophyllum spicatum, Nuphar lutea, Potamogeton spp.), and we describe some new localities of species for which previous data – concerning the micro-region – came exclusively from gravel pits (e.g., Carex secalina, Cyperus glomeratus, Gnaphalium luteoalbum, Najas minor, Typha laxmannii). We discuss our results in the concluding section of the paper, taking into account previous floristic data as well.