This review highlights the progress made in recent years on biosensors aimed at detecting relevant analytes/markers of food peroxidation. Starting from the basic definition of biosensors and the chemical features of peroxidation, here we describe the different approaches that can be used to obtain information about the progress of peroxidation and the efficacy of antioxidants. Aptamers, metal–organic frameworks, nanomaterials, and supported enzymes, in conjunction with electrochemical methods, can provide fast and cost-effective detection of analytes related to peroxidation, like peroxides, aldehydes, and metals. The determination of (poly)phenols concentrations by biosensors, which can be easily obtained by using immobilized enzymes (like laccase), provides an indirect measure of peroxidation. The rationale for developing new biosensors, with a special focus on food applications, is also discussed.