The present study aims to address the effect of soil-structure interaction (SSI) on the seismic performance of an urban building with a steel frame (hinge/shear connection) and concrete shear walls in the Top-down construction method. In the current research, in order to interpret the numerical linear analysis of interaction effects, simulations of soil and structure were conducted in the direct and three-dimensional model using finite element ABAQUS software, and the fixed-base structure model was analyzed on the ABAQUS. To the modeling of an urban structure, all the structural details are taken into account, including the simple connections of beam-to-beam and beam-to-column connections, connections of shear walls to the floor and strip foundations and the Top-down method. The site spectrum was founded in the location of the site and three records in three directions were employed to carry out the seismic time history analysis. In this study some importance features which were scrutinized were base shear forces, torsion and inter-story drifts. The results illustrated that the SSI caused a change in the mode shape of the structure. Thus, the maximum value of the drift in the fixed-based model was formed in the roof, while in the SSI model, it occurs in different stories. The building torsion showed a rise as a result of the SSI, which is a non-conservative value comparing with the fixed-base assumption of the buildings founded on rigid foundations. As well as this, the SSI model experienced a significant decline in the base shear and drift in stories above the ground compare to the fixed base model. Afterwards, as specified in the seismic building codes, several important seismic

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