Abstract Pollen analysis has been performed on a 98 m core recovered in the palaeo-lake of Acerno (Campania, Italy). This study identified four main vegetation zones that can be correlated with Quaternary climatic events. In particular, one interglacial–glacial cycle was recorded in the succession the duration of which was estimated at around 100 ka. The interglacial period (Zone 2) is characterized by large amounts of deciduous and altitudinal forest elements; Mediterranean xerophytes are rather rare because of the distance from the palaeo-sea coast. The interglacial–glacial transition (Zone 3) shows a very rapid decrease of the arboreal taxa and a contemporaneous increase in the frequency of the non-arboreal element. The genus Pinus , excluded from the pollen totals, shows its highest percentage and concentration values during the transition. The glacial period (Zone 4) is characterized by the dominance of herbaceous and steppe elements, and by rather large amounts of Pinus . The floral composition of the analysed succession allows a late mid-Pleistocene age to be proposed for the Acerno palaeo-lake.