Abstract Quantum dot-based optical biosensors represent a significant advancement for detection of mycotoxins that are toxic secondary metabolites produced by fungi and pose serious health risk effects. This review highlights the importance of detection of filamentous fungi such as Aspergillus, Penicillium, Fusarium, Claviceps, and Alternaria in mycotoxin production, leading to contamination of agricultural products and subsequent health issues. Conventional detection methods such as thin-layer chromatography (TLC), high-performance liquid chromatography (HPLC), gas chromatography (GC), and enzyme-linked immunosorbent assay (ELISA) are discussed with their respective advantages and limitations. Then the innovative use of quantum dots (QDs) in fabrication of biosensors is discussed in the present review, emphasizing their unique optical properties, such as size-tunable fluorescence and high photostability. These properties enable the development of highly sensitive and specific biosensors for mycotoxin detection. The application of QD-based biosensors, based on their applied bioreceptors including antibodies, molecularly imprinted polymers (MIPs) and aptamer, is explored through various detection strategies and recent advancements. The review concludes by underscoring the potential of QD-based biosensors in providing portable, cost-effective, and efficient solutions for real-time monitoring of mycotoxin for enhancing food safety and protecting public health.