This paper analyzes food safety as a product attribute and the complicated modern food supply system.Based on the analysis, we put forward the necessity of introducing traceability systems in food supply chain to solve the information asymmetry problem in food market.Further,this paper studies the impact of traceability systems on stakeholders of food safety.We suggest that the mechanism that makes traceability systems play a role in food safety risk control is that it provides clear liability of a firm to food safety incidents and incentives arisen from preserving and strengthening the reputation of a firm.