The invention provides an ultrahigh frequency radiation characteristic simulation method of an oilpaper capacitance bushing lifting seat. The method comprises that a 3D model of the oilpaper capacitance bushing lifting seat is established; grid initialization and self-application sub grid division are carried out on the 3D model based on a finite difference time domain method; a simulated excitation source is arranged; data observation points are arranged; collection data of the data observation points in the simulated electromagnetic wave time-domain spreading process within preset time is obtained; and the ultrahigh frequency radiation characteristic of the oilpaper capacitance bushing lifting seat is obtained according to analysis on the collection data. The simulation method can fit the engineering practicality, and compared with onsite test, the method is safer, and the economic and implement performance is higher. and the invention also provides a simulation system realizing the method.