The concentration of TVOCs in public transportation in the spring and summer of 2018 was measured. Public transportation measured the concentration of TVOCs on six subway lines in Seoul, two lines of high-speed trains, and intercity buses. The measurements were taken during the operation of each route of the surveyed public transportation from the origin to the destination. In addition, the measurement time was divided into the congestion time and the non-congestion time. In the spring of 2018, in the order of subway, train A, train B, and intercity buses, TVOC concentrations during the congestion time zone were 205.9 μg/m3, 121.3 μg/m3, 171.1 μg/m3, and 88.7 μg/m3, respectively. During the non-congestion time zone, the concentrations were 177.2 μg/m3, 108.8 μg/ m3, 118.2 μg/m3, and 126.1 μg/m3, respectively. In the summer of 2018, TVOC concentrations in the order of the aforementioned transportation modes during the congestion time zone were 169.8 μg/m3, 175.8 μg/m3, 78.0 μg/ m3, and 185.3 μg/m3, respectively. During the non-congestion time zone, the concentrations were 210.8 μg/m3, 116.1 μg/m3, and 162.7 μg/m3, respectively. An analysis of BTEX concentration among VOCs in public transportation in descending order were followed by toluene > xylene > ethylbenzene > benzene. Toluene, which has the highest concentration among the BTEX compounds, was found to be 12.86 μg/m3 to 91.41 μg/m3 during spring congestion time and 7.10 μg/m3 to 39.52 μg/m3 during non-congestion time. During the summer congestion time, the concentration was 6.68 μg/m3 to 249.48 μg/m3 and 13.23 μg/m3 to 214.5 μg/m3 during the non-congestion time. The concentration of benzene was mostly less than 5 μg/m3 in transportation. Particularly in the case of toluene, the concentration is significantly higher than that of other VOCs. Accordingly, further study of toluene exposure hazards will be needed. Five percent of the surveyed TVOC concentrations exceeded the recommended indoor air quality standard of 500 μg/m3, and all 13 cases representing this percentage were found in the subway. In addition, nine of the 13 cases that exceeded the recommended standard were measured during congestion time. Therefore, VOCs in public transportation vehicles during congestion time need to be managed.