The coal-dominated energy structure has not only fueled China's rapid economic development, but also brought great pressure on China. Promoting energy transition is among the great challenges for China. As one of the most developed megacities in China, Beijing promotes energy transition intensively. In this study, we explored the trends, socioeconomic drivers and environmental impacts of the energy transition process in Beijing during the decades. We found that Beijing's energy transition has gone through four typical stages. After a parallel growth between the economy and coal-dominated energy consumption at beginning, the growth rate of energy consumption has gradually slowed down since 1996. Between 2000 and 2007, the energy structure became relatively balanced and diversified, driven by the changes of energy intensity, energy structure, and final demand composition, along with the economic structure's shift from heavy manufacturing to service. Thereafter, economic development was seriously decoupled from direct energy consumption, and the de-coal trend had made remarkable achievements. SO, and NO,, emissions have declined significantly since 2007. Diversified energy structure based on the de-coal trend, cleaner energy, and economic restructuring promotes energy transition. Meanwhile the feasibility of implementation also should be considered in other cities' energy transition process in China.