Food traceability is more and more important in the food safety, and as a potentially effective tool in the food traceability, DNA barcode is developing rapidly in recent years. This review describes the applications of DNA barcode in food safety especially in food traceability. From the concept of DNA barcode to food test, food traceability and prevent commercial fraud in food. DNA barcode can ensure food safety and prevent commercial fraud, but to the large-scale applications, there is still a long way to go.