Unnecessary fuel consumption and vehicle emissions due to transit bus idling increase local government subsidies provided to bus companies in South Korea and negatively affect citizen health. In this study, we analyzed the temporal and spatial distributions of transit bus idling using transit bus operational information collected via a digital tachograph. Transit bus management strategies were then proposed on the basis of analytical results. Specifically, all idling times were calculated by analyzing the driving records of all buses operating in Gwangju for 1 day on weekdays, and the idling data were classified into depot, bus stop, and road datasets on the basis of the idling occurrence location. The classified datasets were used to analyze the idling characteristics and fuel consumption, and CO2, THC, CO, and NOX emissions were calculated using the MOtor Vehicle Emission Simulator (MOVES) model. The results show that the largest proportion of total idling time is idling caused by the traffic situation on roads, accounting for 74–81% of the total. However, 12–18% of the total idling occurred at bus stops and 4–14% of the total idling occurred in depots. The compressed natural gas consumed by all transit buses during idling for a single day was 7402 m3, which was estimated to cost approximately $4585.