Ten sandy beaches at the Belgian coast were sampled monthly on a qualitative basis. Six of them were also sampled quantitatively every two months. In total, 130 species were encountered, 38% of them occur only in 1 or 2 localities, 32% have a more general distribution (in 3 to 7 localities) and 30% are found in at least 8 localities, Schizorhynchia generally from the dominat taxon in number of species, followed by the Proseriata. In Knokke and Het Zwin, equal numbers of species were found for both taxa. Mariakerke, Bredene, Knokke and Het Zwin have the most diverse turbellarian fauna's, with the lowest dominance ratio's. In the semi-exposed beach of Oostende the fauna is slightly less diverse, dominated by a few species, while the sheltered beach in Heist clearly has the least diverse fauna, strongly dominated by one species, Archilopsis arenaria.