A numerical simulation to evaluate responses of seismically isolated buildings during the Great East Japan Earthquake in 2011 is carried out in this study. The numerical simulation includes non-linear analyses of the base isolation system based on a Simple Bi-Linear Model and Modified Bi-Linear Model, which take into consideration the degradation of the secondary stiffness. From the result of those analyses, it was proved that the response of seismically isolated buildings is as follow: the base isolation system has non-linear behavior and the upper-structure behaves in the elastic range, because the base isolation decouples the movement from the ground motion, the displacement concentrates at the isolation level and the upper-structure behaves as a rigid body. A proposal for the design procedure for base isolated buildings in Peru is made in this study. This procedure is based on the recommendation of CIB (International Council for Research and Innovation in Building and Construction), using the preliminary design procedure for seismically isolated buildings (CW2012) and taking into consideration the Peruvian seismic code.