As a result of the continuous convergence between the two African-European plates, the Mediterranean region was flooded again at the Miocene-Pliocene boundary (after the Messinian salinity crisis) by Atlantic waters following the collapse of the Gibraltar Strait. The nature of the water mass exchange between the Atlantic and the Mediterranean during the early Pliocene is still unclear. For this reason, the Moroccan Mediterranean coast, in general, and the Neogene Basins of the northern Rif are key areas for understanding Atlantic-Mediterranean relations and characterizing the Pliocene sedimentary deposits that recorded the return of the sea. In order to obtain information on the paleoenvironment and paleoclimate evolution during the Pliocene, a palynological study was carried out on the Sidi Dris section located on the southern shore of the Alboran Sea (Boudinar Basin). The pollen analysis of the Sidi Dris section reveals the presence of relatively diverse vegetation, dominated by continental inputs (pollen and spores) compared to marine inputs (Foraminiferal chitinous tests, dinoflagellate cysts, and Acritarchs). This implies that the marine environment is epicontinental and shallow, receiving fluvial inputs. These assemblages also indicate warm surface water conditions. The evolution of distality markers in this section shows the alternation of proximal to distal neritic environments. The vegetal landscape is open, with sub-desert herbaceous vegetation colonizing the lower altitudes, whereas forest environments developed at mid-altitude. The climate was subtropical, dry, hot on the coast, and humid in higher altitudes.