Food is the most basic material for human survival and development, and food safety is closely related to people’s health and also directly or indirectly affects economic development and social stability. In order to achieve rapid, simple, inexpensive, and universal detection of food safety, cellular biosensors combined with functional nucleic acids are becoming a powerful tool for real-time detection in the field. This chapter describes the current development status, classification, applications, and development prospects of cellular biosensors in food safety and provides a theoretical basis for its subsequent research.