Mycotoxins such as ochratoxin A, aflatoxin B and others are dangerous food contaminants that usually occur in trace amounts from nanograms to micrograms per gram of food. Therefore high sensitive methods are necessary for their detection. The conventional methods such are high-performance liquid chromatography (HPLC), mass spectroscopy are rather expensive and time consuming, therefore biosensor technology is rather promising for rapid detection of toxicants in field conditions, far from specialized laboratories. Among biosensors based on affinity of monoclonal antibodies or DNA aptamers to mycotoxins are of special interest, because provide sensitivity of detection that is better than allowable quantities of toxicants in food. While antibodies are traditional receptors in biosensors, aptamers are novel biopolymers with the affinity comparable to that of antibodies. However in contrast with antibodies, aptamers are more stable and the biosensors based on DNA aptamers can be regenerated which allowing their multiple use. This contribution reviews recent achievements in development affinity biosensors for detection ochratoxin A.