Sulfur hexafluoride (SF 6 ) has been widely used in various kinds of equipments in the power system because of its outstanding capability of electric insulation and arc extinguishment. SF 6 is also one of the strongest greenhouse gases. Due to equipment maintenance and retirement, SF 6 gas leakage and emission from electric equipments is unavoidable. Aiming at developing a low carbon power system, SF 6 usage and leakage should be estimated. This paper reviews and analyzes the ways by which SF 6 gas could leak into the atmosphere. On this basis, a model for estimating the amount of SF 6 emission by electric equipments is presented. Based on the practical data from Guangdong provincial power system, SF 6 emission is compared at the value of equivalent carbon dioxide with generation side CO 2 emission. Moreover, future SF 6 emission is estimated based on Guangdong power system planning scheme. The proposed methodology is helpful to identify the contribution of Greenhouse Gas emission from diffident parts in power system. Useful suggestions for future work about SF 6 management are discussed.I.