It is stating the obvious that China is having what it deems as a „peaceful rise‟ in the global arena. Many scholars believe that the most important dimension of China's Rise in recent years is in its economic front, and that China's foreign policy trend indicates some economic programs encouraging the country to enter the Middle East. During the recent decade, energy security has been significantly important for China and has become her main priority concerning the Middle East and Iran is one of its leading allies in this regard. This paper examines the role of energy in Iran-China relations. Its main argument is that energy and its secure supply is a determining factor in China's policy for developing relations with Iran. Qualitatively driven and relying on the secondary sources of data, the paper uncovers that because of a lack of internal oil resources, China has adopted a policy of getting energy supply from external resources and for such supplies, Chinese leaders have always had an eye on Iran. It equally discovered that following the sanctions imposed on Iran, China could particularly pay for energy imports from Iran through barter, hence expanding its exports to Iran. The paper concludes that energy security is significant in relations between countries and that it remains at the center of Iran-China ties sanctions notwithstanding.