Paleoceanographic conditions across the Valanginian Weissert oceanic anoxic event were reconstructed for the first time on the central Moroccan margin from a quantitative-based calcareous nannofossil study. Two onshore successions in the Essaouira-Agadir Basin and one offshore from DSDP Hole 416A were studied, providing a proximal-distal transect on the central Moroccan margin. The paleoceanographic conditions were reconstructed in an accurate chronostratigraphic framework. The sedimentary evolution of the Essaouira-Agadir Basin shows that sea-level variations controlled the paleogeographic context, clastic input, and nutrient availability. A thick photic zone and mesotrophic conditions favored the development of a diverse nannofossil community before the Weissert Event in the early Valanginian. In all studied successions, a collapse of the nannofossil community was recorded during the onset of the Weissert Event at the early-late Valanginian transition, and was caused by a major sea-level fall. The nannofossil community gradually recovered and reached its highest nannofossil production associated with high surface-water fertility during the Weissert Event in the late Valanginian. This eutrophication is coeval with the high and stable delta C-13(carb) values of the carbon-isotope positive shift. After the Weissert Event, surface-water fertility and nannofossil production decreased but remained higher than during the early Valanginian. Additionally, the nannoconid decline started in the early Valanginian and was linked to a low sea-level. Their recovery in the early late Valanginian occurred during conditions of high sea-level and of high surface-water fertility. The central Moroccan margin is integrated into a global paleoceanographic reconstruction.