Abstract: Objective This paper puts forward suggestions on the development of in vitro diagnostic reagents and supervision measures for the post-marketing products, so as to further improve the quality of in vitro diagnostic reagents and ensure the safety use of medical device. Methods This paper summarizes the quality of in vitro diagnostic reagents and analyzes the causes of the problems, according to the results of the national medical device supervision and inspection in 2020. Results The overall quality of in vitro diagnostic reagents for national medical device supervision and inspection in 2020 is stable and the unqualified detection rate is 1.6%. However, there are some problems. For example, the management of raw materials is unscientific, the faultiness in the preparation of reference materials, the understanding of standards is unthorough, and the management of instructions is unimportance. Conclusion It is suggested that manufacturers of in vitro diagnostic reagents should improve the binding force of the quality management system, strengthen the awareness of risk management, attach importance to communicate with regulatory authorities, study standards sufficiently and strengthen the management of instructions. It is also suggested that the regulatory authorities should strengthen supervision and inspection, and further complete the evaluation guidance and standard publicity and implementation.