The aim of the study was to determine the effects of anabaenopeptin-B (ANA-B), aeruginosin 98 (AER-B) and their binary mixture (ANA-B+AER-B) on biomarkers of oxidative stress (glutathione (GSH), superoxide dismutase SOD, total nitric oxide (NO), catalase (CAT), lipid peroxidation (LPO), hemoglobin (Hb) level, heat shock protein HSP70 and tyrosine phosphatase activity in three aquatic invertebrates Brachionus calyciflorus, Tham- nocephalus platyurus and Chironomus aprilinus. The results revealed alterations of the tested parameters in response to the tested cyanobacterial metabolites with various interactions in the mixtures. The study suggests that During natural exposure to cyanobacterial metabolites and their mixtures different responses to oligopeptides in the group of may occur in aquatic invertebrates. Total effects of mixtures may depend on the structure, type of components and sensitivity of the exposed invertebrate species.