Since electric power engineering is a vitally important lifeline engineering

the careful design of ground motion parameters of electric power engineering site have great practical values. To determine ground motion parameter

one of the methods is the statistical empirical method corresponding to code and another is seismic response analysis for soil layers. In this paper

taking a certain electric power engineering site as an example

probability method of seismic hazard analysis considering sites earthquake environment of surrounding area and rock ground motion attenuation is used to determine the bed-rock peak ground motion accelerations and the acceleration response spectrum with different exceedance probabilities in the area. Considering the effect of soil nonlinear dynamic property of soil layer

the site effect and earthquake response of soil layers are also analyzed by one-dimensional equivalent linearization wave motion model. And design ground motion parameters of soil layers for exceedance probability 63%

10% and 3% in fifty years are given. The result is very useful to the design of earthquake engineering of this project. The main conclusions are:（1）. Because of the lack of strong earthquake record in the area

the formula of the bedrock ground motion attenuaion relationship in the area is obtained by selecting the seismic intensity attenuation relationship suitable to this area and the rock ground motion attenuation relationship in the west United States. The bedrock peak acceleration exceedance probability 63%

10% and 3% in fifty years are 0.026 g

0.063 g and 0.088 g respectively.（2）. The seismic waves are either amplified or absorbed while they go through the soil layers

which results in the ground peak acceleration magnified by the covering soil layers. The ground peak acceleration value at the site with exceedance probability 63%

10% and 3% in fifty years are 0.044 g

0.083 g and 0.114 g

enlarged to a certain extent. （3）. Compared with the values in some codes

the calculated one are more precise. For the electric power engineering site

special attention should be paid to the designing seismic ground motion parameters.