Seasonal freezing, causing significant change in the stiffness of soils and its potentially significant impact on the seismic response of soil-structure interaction systems, is an accepted principle. Since many masonry structures in cold regions are located in seismic active zones, determining the effect of seasonally frozen soil on the stochastic response of masonry structures subjected to random seismic excitation becomes an important structural consideration. In response to this need, a three-dimensional finite element model of a masonry minaret-soil interaction system, which considers viscous boundaries, becomes a useful tool for analyses. For the model, the power spectral density function represents random ground motion, applied to each support point of the three-dimensional finite element model of the masonry minaret-soil interaction system. The current research conducts a parametric study to estimate the effects of the seasonally frozen soil on the stochastic response of the masonry minaret-soil interaction system. The analyses encompass different ground temperatures for sand and clay soils and different frozen soil thicknesses. In addition to these, the analyses include three different soil types in order to investigate the effect of foundation soil properties on the stochastic response of the interaction system. Finally, this study concludes that seasonally frozen soil's effects cause considerable changes in stochastic behaviour of masonry minaret-soil interaction systems. (C) 2009 Elsevier B.V. All rights reserved.