Energy has been one of the key factors influencing the international relationships in the Twenty First Century. In recent years, the energy demand increases rapidly in developing countries, while the world oil price also rises significantly; therefore, the energy problem regains people's attraction all over the world. As for China, who suffered from the energy unbalance of supply and demand, has to give up the previous self-sufficiency policy and find other ways for energy supply resources; as a result, the general environmental background for China's energy diplomacy is also offered. This paper mainly analyzes the background for the formation of China's energy diplomacy and its connotation as well.