This study was aimed to provide the controlled terminology for adverse drug reactions by selecting an appropriate internationally standardized classifications (WHO-ART or MedDRA). We collected the relevant information on ADR terminology systems including WHO-ART and MedDRA by online searching and visiting pharmaceutical companies and WHO UMC (Uppsala Monitoring Centre, Uppsala, Sweden). For MedDRA, project leader directly communicated with the officer of MSSO (Maintenance and Support Services Organization). Collecting all the pertinent information, two possible terminology classifications or systems (WHO-ART and MedDRA) were compared in the views of acceptability, cost-effectiveness and international feasibility and reviewed by the consultation committee and finally WHO-ART was selected.