This study investigates thermal bridging in the adhesive-bonded structure via numerical simulations, with a focus on the effects of adhesive thermal conductivity and structural thickness. The thermal conductivity difference between the adhesive and aerogel materials drives a pronounced enhancement of heat flux density in the adhesive layer, inducing steep temperature gradients at their interface, which forms localized high-temperature zones and destabilizes the interfacial temperature field. A nonlinear relationship is observed between adhesive thermal conductivity and the peak temperature at the bottom surface, reflecting inhibited heat transfer due to bidirectional thermal coupling with the aerogel. Notably, the extent of the thermal bridging zone remains insensitive to changes in adhesive thermal conductivity. Structural thickness strongly affects both the extent of thermal bridging and transient thermal response. A 10 mm-thick configuration exhibits a 50% broader influence zone than its 5 mm counterpart. These results offer valuable insights for optimizing thermal protection systems by balancing material and geometric design to mitigate thermal bridging effects.