OBJECTIVE： To put forward suggestions for improving the supervision of phase Ⅳ clinical trials in China. METHODS： According to summarizing the post-marketing research in America， FDA’s supervision （including key elements， supervision flow， auxiliary supervision system and enforcement measures） for drug post-marketing research in America was analyzed， and suggestions for the supervision of phase Ⅳ clinical trials in China was put forward. RESULTS & CONCLUSIONS： The drug post-marketing research in America included post-marketing commitment research （PMR） and post-marketing requirement research （PMC）. The key elements included supervision subjects （dealt by Office of New Drugs affiliated to Drug Evaluation and Research Center）， key document （including the documents helping FDA and applicants reached a research agreement， and documents for process tracking and supervision in identified studies） and important time node. The supervision flow included developing drafts and reviewing reports. FDA had established PMC/PMR database， which was used as auxiliary supervision system， and relevant enforcement measures were respectively developed for PMC and PMR. Relevant supervision departments in China should converse the supervision ideas， give full play to the government’s guidance and supervision， enhance the connection of supervision between pre- and post-marketing， specially develop phase Ⅳ clinical program， establish system for phase Ⅳ clinical trial data， enhance whole process supervision， draw lessons from “pre-process plan， dynamic tracking in the process， and post-process decision according to law” of FDA to improve the supervision of phase Ⅳ clinical trials in China.