These paper investigated the relationship between economics development and energy demands based on Energy Kuznets Curve (EFC) in China. The results show that, the prospects of economics and energy demand in China in further will undergo three important stages to 2050.The peak of energy demand maybe around 2035 and the corresponding total energy demand maybe amount 5.7 billion tce. In 2035, the GDP per capital maybe about 17000 (2005 US$) and the urbanization will reach a relative high level. It is urgent for China to take actions to curb the increasing total energy consumption.