This study was a time activity pattern assessment focused on transportation in subpopulation groups using the ‘Time-Use Survey’ conducted by the National Statistical Office in Korea in 2009. The time activity patterns of transportation on weekdays were analyzed, looking at average travel time in Seoul, Gyeonggido and the whole country. Various subpopulation groups were classified such as students, the elderly, workers and housewives. The population of Gyeonggido had a higher average transportation time than that of Seoul. Workers showed the highest weekly average travel, while the students group showed the lowest tendency. The times spent in walking, bus, subway and taxi were the highest in areas other than Gyeonggido, where the use of private vehicles such as car was higher. Therefore, exposure to hazardous air pollutants may vary depending on the transportation method and time spent. This results indicate that time activity pattern assessment on transportation may be an important element of exposure assessment. Keywords : Time activity pattern, Transportation, Subpopulation groups, Exposure