The prediction of ground motion fields for potential earthquakes is important for urban planning and regional seismic hazard assessment. In this paper, the prediction of MW
≥7.5 ground motion is carried out for the Xiadian fault. Firstly, the earthquake source is set based on the full rupture patterns to cover the unknown information of the Xiadian fault as much as possible. Then the ground motion field in the study area is simulated due to the MW
≥7.5 earthquake on the Xiadian fault. Furthermore, the spatial distribution of ground motion at each site is filtered based on the quantile method, and the distribution characteristics of peak ground acceleration and peak ground velocity for the inclusion of uncertain sources are discussed. The results show that an MW
7.9 earthquake on the Xiadian fault will produce the strong ground motion in Tongzhou district and Beijing center zone. After that, the spatial distribution of the ground motion due to the MW
7.5 earthquake from the simulated source is discussed. The results illustrate that the simulated ground motion from the two types of sources can corroborate each other for the same magnitude. Our study provides a method for the earthquake hazard predictions due to the potential sources with some unknowns.