Estimation of earthquake clusters expected to occur in a certain area together with their probability occurrence are required to evaluate the seismic risk to railway structures and vehicles. In this study, a calculation method is proposed for obtaining a set of earthquake time histories and their occurrence probabilities by combining a seismic hazard analysis and estimation of strong motion. Earthquake ground motion in the Tokyo region was then estimated using the proposed method in order to create an example of its applicability. It was then confirmed that seismic risk to railway structures and vehicles can be evaluated by using the proposed method.