Abstract: Ground motions are highly coupled with site conditions. Dynamic soil properties such as shear modulus and damping are the most prominent factors of amplification phenomenon during earthquakes. The shear modulus degradation and damping ratio curves have been developed based on the nonlinearity soil from hysteresis loops. Effective confining pressure and plasticity index are governing factors that effect the nonlinearity soil behavior. In this study, the shear modulus degradation and damping ratio curves were derived from cases. The first case was based on only effective confining pressure, whereas, the second case was based on effective confining pressure and plasticity index. These two models adopted equivalent linear method for the site response analyses. A set of outcomes are introduced to show the influence of the two models of curves in the site response.