Abstract: Switch cabinet fire accident is an important safety hazard in the power system operation.In the current commonly used fire extinguishing methods,ultra-fine dry powder and hot aerosols are difficult to clean up after extinguishing fires,which will damage electrical equipment. Heptafluoropropane gas fire extinguishing agent has poor environmental protection and has been restricted or controlled.While erfluorohexanone is very friendly to the environment and safer to human body,which is a clean gas fire extinguishing agent. In order to verify the fire extinguishing effect of the new environmentally friendly fire extinguishing agent perfluorohexanone on the switch cabinet fire accident,a 10 kV typical switch cabinet commonly used was selected as the test object,and a perfluorohexanone fire extinguishing test platform was built.The data collection was carried out by usage of thermocouples,thermal radiometers,oxygen concentration detectors,composite gas analyzers and other test equipment.The test results show that the perfluorohexanone fire extinguishing system can quickly extinguish the switch cabinet fire,which can meet the requirements for the prevention and control of the switch cabinet fire. This paper provides a certain reference for the promotion and utilization of perfluorohexanone in power transmission and transformation equipment.