The invention discloses a sulfur hexafluoride (SF6) gas decomposition characteristics based partial discharge characteristic identification method. The method includes the steps of S1, detecting whether purity of SF6 gas is up to the standard or not; S2, detecting content of impure gases in the SF6 gas; S3, selecting the decomposition characteristics of the SF6 after partial discharging for detection and identification. The sulfur hexafluoride (SF6) gas decomposition characteristics based partial discharge characteristic identification method has the advantages that properties and characteristics of insulation defect types in SF6 equipment can be accurately known and mastered so as to specify an effective maintenance strategy and guarantee safe and reliably running of the SF6 equipment.