From the standpoint of traditional DEA model and taking environmental pollution outputs into account, according to Chinese provincial panel data from 2005 to 2010, we have analyzed China's energy efficiency by using different cross-evaluation methods. The results have shown the low-level of China's energy efficiency and significant differences of provincial energy efficiency. Besides, there is a pattern of high energy efficiency in the eastern region and low energy efficiency in the western region. In addition, China's energy efficiency has an upward trend during the 11th Five-Year Plan, but the gap of energy efficiency between eastern and western regions has a trend of widening.