The soil-steel composite bridges, typically ranging from 3 to 25 m, can be used as an effective alternative for short-span bridges and culverts. They can meet the design and safety requirements as for traditional bridges, more rapidly and at lower costs. For these reasons, soil-steel bridges are increasingly being used in road and railway projects in many parts of the world. Due to the fact, the typical static and dynamic analyses of such bridges were already conducted many times, this paper focuses on the results of the numerical analysis of soil-steel composite bridge under seismic excitation. For these purposes a bridge with span of 17.67 m and height of 6.05 m was selected. Numerical analysis was conducted using the DIANA program based on finite element method. The density and Young modulus of the backfill were varied in the numerical models. A linear model with El Centro records and Time History analysis were used. The conclusions drawn from the study can be helpful for designers and researchers dealing with the soil-steel bridges, especially for the projects situated in the seismic areas.