AbstractThe nesting biology ofChalybion turanicum(Gussakovskij, 1935) has been studied, with a total of 31 nests being examined. All studied nests were located inside the old nest cells ofSceliphron destillatorium(Illiger, 1807). Each nest ofCh. turanicumconsisted of a single cell. Females hunted for spiders, with 18 species in five families being identified among their prey. Two most abundant victim groups were Theridiidae (eight species, 54% of specimens) and Araneidae (seven species, 33% of specimens) spiders. A spider number stored in a cell varied from five to 31 (mean = 17.6 ± 5.4). In the Crimea,Ch. turanicumhas one generation per year with reproductive success of 67%. Two species of the nest parasites were reared from cells ofCh. turanicum:Chrysis taczanovskiiRadoszkowski, 1876 andAcroricnus seductor(Scopoli, 1786).Chalybion turanicumis the seventh invasive species of Sphecidae naturalized in Europe.