As SF6 mixture gas gradually replaces pure SF6 gas as insulation gas for switch equipment, the decomposition products of SF6 mixture gas such as Quantitative analysis have been put on the agenda. Although SF6 gas mixture is similar to high purity SF6 in physical chemistry characteristics, there are great differences in decomposition product gas analysis algorithms. If we still use high purity SF6 gas decomposition product detection equipment and algorithms, the result will cause the quite big measurement error, can not satisfy the measurement precision request. The Gas chromatography can be used for quantitative and qualitative analysis of the characteristic gas components of the decomposition products by valve switching, selection of supports, and optimization of chromatographic conditions. The Sulfur hexafluoride Gas chromatography enables the detection of decomposition products of Sulfur hexafluoride gas mixtures under laboratory and field conditions. It is convenient to find and deal with the defect and hidden trouble of the equipment, and carry on the comprehensive condition evaluation. This can not only ensure safe and stable operation, but also provide technical support for power grid construction.