The Messinian section of Sidi Haj Youssef (Boudinar basin- NE. Morocco) with alterancy of marl and diatomitic levels, is very rich in benthonic foraminifera and wich are represented by 102 species. The quantitative studies reflected different conditions in relation to the diatomitic and marls levels. The association of foraminifera and paleoecologic indices, in diatomitic levels, are according with de upwellings influences and the associations in the marl levels, with normal marine conditions. By the other hand, the associations reflected the bathymetric conditions during the Messinian