Okadaic acid （OA） is widely distributed in seafoods and is a remarkable threat to food safety. Owing to its high toxicity， small size， and low molecular weight， obtaining antibodies against OA is a complex and difficult task. The aptamer SELEX technology can be used to achieve high affinity and single aptamer sequences for small molecules. Accordingly， this technology has several advantages for the detection of shellfish biotoxins. This review highlights the applications of biosensors based on OA aptamers， such as colorimetric sensors， fluorescent sensors， electrochemical sensors， and so on， in the rapid detection of OA. A summary of the performance and application potential of these sensors is provided， and the development direction of aptamer sensors is discussed to better promote their development and application.