The World Meteorological Organization/Global Atmosphere Watch (WMO/GAW) Regional Dobson Intercomparison for Asia was held from 7 to 25 March 2016 at the Aerological Observatory in Tsukuba, Japan in close cooperation between WMO and the Japan Meteorological Agency (JMA) which serves as the Regional Dobson Calibration Center for Asia for total ozone. The purpose of the activity was to ensure traceability to the regional standard Dobson spectrophotometer (no.116) through the intercomparison with those Dobson spectrophotometers (no. 75, Xianghe/China; no. 90, Bangkok/Thailand; and no. 100, Quetta/Pakistan) operated in Asia member countries. Four experts from China, Pakistan and Thailand participated in the intercomparison, which was conducted under the direction of a skillful expert from the National Oceanic and Atmospheric Administration (NOAA, USA) and a former ozone coordinator in JMA. The experts also instructed the participants in the proper operation of the instruments and data processing at their home countries. Although the weather was changeable during the period, the intercomparison was successfully performed during the clear days.