The nonlinear buckling behaviors of sandwich functionally graded graphene reinforced composite (FG-GRC) laminated toroidal shell segments with corrugated core under lateral pressure in thermal environment are reported in this study. Three distributed types of the FG-GRC face sheets and two forms of corrugation including the trapezoidal and round corrugations are considered. By adding the thermal forces into an existing equivalent technique, the behavior of the corrugated core is modelled. The nonlinear formulations can be obtained by using the nonlinear Donnell shell theory taking into account the shell-foundation interaction. The Ritz energy procedure is used for three states of deflection to obtain the postbuckling curve expressions of the load-maximal deflection. The bifurcation buckling type of critical buckling pressure is obtained in the explicit form. The numerical examinations present the significant effects of corrugated core and FG-GRC laminated face sheets on nonlinear buckling behaviors of shells.