Using flow cytometry we explored the cytogeography of Seseli libanotis (Apiaceae) from central Europe and several adjacent areas. We detected diploids and tetraploids, but no triploids. Diploids are distributed across nearly all study areas, whereas tetraploids occur in Czechia, the Pannonian lowlands of northeastern Austria and western Slovakia, in southeastern Slovakia, in the Eastern Carpathians and the Apuşeni Mts in Romania, and in Croatia. The distribution of cytotypes is nearly allopatric. Only in some regions on the northern border of the Pannonian basin, in southern Poland and in Romania they are parapatric. Only one mixed-ploidy population (located in Poland) was detected. In Czechia and Slovakia, we did not find differences in the elevational distributions of cytotypes; tetraploids, however, seemed to have a broader elevational range and slightly prevail at lower elevations. Using sequencing of the trnL-trnF region of cpDNA we detected high haplotype diversity with no relation to cytogeography (longitude, latitude or elevation).