The study concerned the ability of human (HSA), pig (PSA) and sheep (SSA) blood serum albumins to bind ochratoxin A (OTA) and roridin A (RoA). Fluorescence spectorscopy and cytotoxicity test MTT with swine kidney cells (SK), susceptible to a wide range of mycotoxins, were used for the evaluation of the mycotoxin-albumin complexes. OTA was found to bind strongly to all the studied albumins, but the nature of the binding was found to be different in all three cases. Binding abilities corresponded with the results of the cytotoxicity test MTT. It was not possible to analyze roridin A with the fluorescence method, since this toxin is nonfluorescent. The MTT test results showed that RoA did not bind to the albumins of any of the examined species and was strongly toxic to the cells. The new complexes OTA created with HSA and PSA are so strong that they may be used as biomarkers for diagnostic purposes.