Paleoecological studies indicate environmental changes during selected time horizons within the Upper Cretaceous sediments from three localities of the Gosau Group in Austria. Foraminiferal assemblages were studied from the localities Grünbach-Neue Welt, Weissenbachalm and Spital am Pyhrn. Paleobathymetric changes have been reconstructed using plankton/benthos ratio, percentual abundances of selected genera ans species diversity. Three depth levels with three groups of dominating species were recognized from the Late Turonian to Early Santonian sediments of the Grabenbach Formation at Weissenbachalm locality. From the Grünbach-Neue Welt area the Grünbach Formation (Early Campanian) and Piesting Formation (Late Campanian-Early Maastrichtian) comprise transitional assemblages from shallow-water, neritic marls to bathyal hemipelagics and turbidites. The character of foraminiferal assemblages of the Weisswasser Formation indicates shallow-water shelf conditions during Late Santonian and Early Campanian. The deeper water Wurberg Formation contains richer foraminiferal assemblages with higher species diversity.