Five acritarch Zones are formally described from the Upper Frasnian-Lower Famennian of Belgium. These are based on the stratigraphic ranges of 14 species and varieties, 5 of which are new: Baltisphaeridium basiconstrictum n. sp., Baltisphaeridium medium Stockmans & Willière, 1974 var. praemedium nov. var., Hercyniana sprucegrovensis (Staplin) Vanguestaine in Kimpe et al. , 1978 var. attonita nov. var., Villosacapsula globosa n. sp. and Visbysphaera (?) fecunda n. sp.The stratigraphic significance of these new acritarch Zones has been deduced from six sections (at Focant, Senzeilles, Sinsin, Hony, Lambermont and Visé, respectively) which possess abundant biostratigraphic control elements such as corals, rhynchonellid brachiopods and conodonts.The new zonation has been tested in the Namur and Campine basins, i.e. in the stratigraphic section northeast of the Station of Huy-Nord and in the Booischot Borehole. Also, the detailed stratigraphy of the sections at Hony, Huy and Lambermont has shown many lithological similarities such as the facies change at the Frasnian-Famennian boundary and oolitic "oligiste" marker bands which are all associated with characteristic faunas.