The purpose of this study was to evaluate the effect of carbon dioxide laser irradiation on the performance of silane coupling agent as an adhesion promoter. The carbon dioxide laser used in this study was Opelaser 03S II, which irradiated the silane coupling agent applied on the adhesive surface of porcelain. Before and after thermal cycling, shear bond strength was measured using a universal testing machine. Without primer treatment, most of the specimens failed adhesively before reaching the end of the thermal cycling period. For the specimens irradiated with carbon dioxide laser after primer treatment, their shear bond strengths before and after thermal cycling were higher than those treated with primer only -with a significantly pronounced difference between these two groups especially after thermal cycling. Therefore, a combined surface treatment which involved silane application followed by laser treatment was feasible and efficacious for chairside porcelain repair.