Japan has notified the WTO Secretariat of its proposed revision of the maximum residue limit (MRL) for mandestrobin (G/SPS/N/JPN/1324), intending to set the MRLs for mandestrobin in aquatic products at 0.02 mg/kg. The external comments pointed out that the scientific evidence provided by Japan contains inconsistencies in the data and discrepancies in the calculated residue levels.. Moreover, establishing MRLs for all aquatic products based solely on experiments with a single species lacks sufficient representativeness. Japan's move may constitute a technical barrier to trade. Domestically, it is recommended to accelerate research and develop testing methods for mandestrobin residues, strengthen related toxicological and metabolic studies, and issue timely risk warnings to export enterprises to ensure smooth trade and protect industry interests.