Deep-sea pollen records from the Western European margin show that during the Last Glacial period (ca. 115-27 ka), regional vegetation oscillated between steppe and open forest in response to the millennial scale climate variability, Dansgaard-Oeschger, (D-O) cycles and Heinrich events (HE), and that the magnitude of the forest expansions during D-O warming events was modulated by orbital parameters. We present new well-chronologically constrained high-resolution marine pollen records from the Gulf of Lion and Bay of Biscay documenting the NW Mediterranean and SW France vegetation response during Marine Isotope Stages (MIS) 4 and 3 (67-33 ka). The vegetation of these regions is reconstructed by pollen analysis.This data set presents the row pollen data of MD99-2343 core.