Abstract: On November 30, 2020, due to the continuous obstruction of the appointment and re-appointment procedures of judges by the United States, the WTO Appellate Body was “shut down” due to the expiration of all judges’ terms. The reform of the dispute settlement mechanism is imminent. DSU stipulates that appeals should be limited to the legal issues involved in the panel report and the legal interpretation made by the panel. In the dispute settlement practice, due to the extensive application of judicial economy principle by panels, certain legal and factual issues remain unresolved. At the appeal stage, if the Appellate Body overturns the panel’s ruling and needs to review these issues instead, it will cause ultra vires questioning due to “completing the analysis of the panel”, or the dispute cannot be resolved due to insufficient facts in the case. A system of remand should be established, and the original panel should hear the outstanding matters that should have been tried by it, so as to resolve the judicial dilemma faced by the Appellate Body. Adding a remand system can prevent the Appellate Body from exceeding its power to perform the functions of the panel, while maintaining the trial interests of the parties, thereby ensuring that WTO disputes are properly resolved to the greatest extent.