Foraminifera are single-cell protists that are found within the fossil record of sedimentary rocks. Triasic foraminiferal assemblages represent a recovery after the Permian-Triassic extinction event. The aim of my thesis was to determine the taxonomic composition of foraminiferal assemblages found in Carnian beds deposited in different trophic or sedimentary settings. The differences in trophic levels demonstrated by variation in test size of Aulotortus friedli. Carnian foraminiferal assemblages were compared with the Norian-Rhaetian assemblages. Four localities were investigated: Lower Julian intertidal beds of Razor Limestone, thin bedded calcarenites within carbonate olistolith, in lower Julian amphiclina beds, near Jesenica, Julian Middle Limestone-Marl Member at Lesno Brdo, and Julian to Lower Tuvalian Tor Formation from Stože section. Field analysis was followed by the preparation of thin sections and determination of microfacies and foraminiferal assemblages. Differences in taxonomical compositions were evaluated using statistical methods (Kruskal-Wallis test, ANOVA, DCA, SIMPER and CVA). The assemblages are composed of following taxa: Duostomina, Aulotortus, Lagenina, Endothyroidea, Duotaxis, Agathammina, Trochammina, Pillaminella, Semiinvoluta, Variostoma, Reophax, Lammeliconus, Planiivoluta, Hoyenella, Tolypammina, Miliolipora, Ammodiscus, Krikoumbilica, Gandinella. Investigated sections demonstrate differences in diversity and abundance of taxa and also differences in test size of Aulotortus friedli. Differences can be attributed to different in trophic levels. The Razor Limestone and calcarenits from the Jesenica locality contain a more diverse assemblage with frequent Duostominidae in Endothyroidea. Average size of the tests of Aulotortus friedli species on Razor Mt. is 0,56 mm, whereas in Jesenica 0,66 mm. The latter could be attributed to sorting. The Middle Limestone-Marl Member of Lesno Brdo locality and the Tor Formation in the Stože section show lower diversity of foraminifera. Individual layers often show high abundance of few genera (Hoyenella and Aulotortus). Lower oxygen content, higher levels of organic matter and fine-grained sediment, found at both localities, could be the cause of smaller test sizes of Aulotortus friedli species (0,42 mm at Stože, and 0,24 mm at Lesno Brdo).