Abstract: Gas insulated switchgear（GIS）ultra-high frequency（UHF）partial discharge（PD）detection instruments are widely used in insulation defect detection and fault warning of GIS equipment,but the accuracy of UHF PD instruments in the diagnosis and identification of insulation defects is usually doubtful. In order to improve the effectiveness of insulation defect diagnosis and identification verification of PD equipment,based on the import of GIS field insulation defect pattern,a device was developed,achieving a reverse output. Firstly,the implementation principle and basic structure of the device hardware design and the implementation method of the partial discharge simulation signal generation unit were introduced.Then,the conversion,loading and sending methods of the field UHF partial discharge signal were presented.Finally,the practicability test for the device was carried out.The test results show that GIS UHF PD signal simulation device can effectively simulate various real discharge signals collected on site and output them effectively,providing a new method for insulation defect diagnosis and identification of GIS UHF PD detection instrument.