Having a clear understanding of transport energy use trends is crucial to identifying opportunities and challenges for efficient energy use for the transport sector. To this date, however, no detailed analysis has been conducted with regard to rapidly growing passenger transport energy use in South Korea. Using bottom-up data developed from a variety of recent sources, we described the trends of transport activity, energy use, and CO2 emissions from South Korea's transport sector since 1986 with a particular focus on its passenger transport. By decomposing the trends in passenger transport energy use into activity, modal structure, and energy intensity, we showed that while travel activity has been the major driver of the increase in passenger transport energy use in South Korea, the increase was to some extent offset by the recent favorable structural shift toward bus travel and away from car travel. We also demonstrated that while bus travel has become less energy intensive since the Asian Financial Crisis, car travel has become increasingly energy intensive. Published by Elsevier Ltd.