Seismic base isolation has become an accepted design technique for buildings to protect against earthquakes. The resilient-friction base isolator (R-FBI) provides a new base isolation system. The response of a planer model of one-storey shear type building isolated by R-FBI system to real earthquake motion under different parametric variations in investigated. The parameters include: time period of the superstructure (as fixed base), mass ratio, and the properties of R-FBI system (1.e. damping, stiffness and coefficient of friction). The responses are compared with those of the corresponding fixed base system in order to investigate the effectiveness of base isolation. It is shown that the R-FBI system is quite effective in reducing the seismic response of isolated structure against earthquake excitation.