Early middle Pleistocene deposits from Łuków, correlated with the Cromerian complex, represent rare bi-partite Ferdynandovian pollen sequence encompassing two interglacial warmings (F1 and F2) separated by F1/2 cooling/glaciation and related to MIS 15–13. The paper presents pollen-based palaeoecological and palaeoclimate investigations in which plant climate indicators were applied. Additionally modern pollen dataset from the Roztocze region was used to evaluate vegetation history in terms of forest communities and presence and abundance of tree taxa sensitive to air temperature and humidity. Climate changes derived from pollen data indicate strong oceanic features of the climate of the fi rst interglacial (F1) resembling those typical for the beginning of the Eemian, followed by cooling (F 1/2) with plant communities typical of the Pleistocene steppetundra, which undoubtedly indicate strong continentality, and subsequent return of more oceanic climate (F2) with mean remperature of the warmest month exceeding 18°C. Both pollen succession and climate changes recorded in the Łuków sediments correlate well with other bi-partite successions known from eastern part of European Lowlands.