This manuscript first gives a separate decomposition analysis on the factors that affect regional energy efficiency in Beijing, Tianjin, and Hebei, China, during 2005-12 based on the logarithmic mean divisia index (LMDI) model, and then makes an in-depth investigation on impact factors in the Beijing-Tianjin- Hebei (BTH) region of China. Energy efficiency is decomposed into carbon productivity, carbon emission coefficient, energy structure, energy intensity, economic output, and reciprocal effect of per capita energy consumption. Different impact factors in various areas have diverse influences on energy efficiency due to the evident regional differences in Beijing, Tianjin, and Hebei. On the whole, the primary positive driver of energy efficiency is the economic output in the BTH region, followed by carbon productivity, carbon emission coefficient, and energy structure. However, energy intensity and the reciprocal effect of per capita energy consumption are the major inhibitory factors. Finally, we emphasize a series of policy implications to speed up the achievement of China’s 12^th Five-Year Plan goal. It also has the vital practical significance of carrying out energy policy and a low-carbon economic development strategy in the BTH region in the future.