Bacterial toxins pose significant food safety risks, contributing greatly for the foodborne outbreaks in most parts of the world. Within the realm of Gram-positive pathogens, notable toxins include the emetic toxin and diarrheal enterotoxins produced by Bacillus cereus, neurotoxins from Clostridium botulinum, enterotoxin associated with Clostridium perfringens, and a family of enterotoxins synthesized by Staphylococcus aureus and certain other staphylococci. These toxins represent pivotal virulence factors for their respective foodborne pathogens, playing a central role in the onset of related foodborne diseases. Diverse in their nature, these toxins exist as proteins or peptides, differing in size, structure, toxicity, toxicological endpoints, solubility, stability, and their affinity for specific food matrices. These variations significantly impact the characteristics of requisite detection methods. Consequently, the detection of these toxins in food samples, or the assessment of toxin production capacity in bacterial isolates, remains foundational to microbial food analysis. Foodborne illnesses caused by Gram-positive bacteria and their toxins pose a significant threat to public health worldwide. Traditional detection methods often involve laborious culturing and biochemical assays, which are time-consuming and expensive and lack real-time monitoring capabilities. Optical biosensors offer a promising alternative for rapid, sensitive, and on-site detection of these toxins in food samples.