ABSTRACT The development of research on loessic sequences of the last glacial- interglacial cycle now allows to localize the numerous sites of the recent phase of the middle paleolithic of northern France in a detailed strati- graphic frame. In the same way, the study of the most complete pedosedimentary sequences leads to a first reconstitution of the paleoenvironments. The distribution of the sites in the three types of climatic phases : Inter- glacial, Early-glacial and Pleniglacial, is characterized by a very clear concentration of the occupations in the first two phases of the climatic cycle. If one takes into account the sedimentary context of each settlement, it is obvious that this repartition of the occupations depends on the type...