Current studies on the thermal effect on the full-range debonding process of Carbon Fiber Reinforced Polymer (CFRP)-steel interfaces are rare and fail to account for residual interfacial friction stress. Therefore, this paper proposes an analytical approach to evaluate the debonding response of CFRP-strengthened steel interfaces under combined thermal and mechanical loads, accounting for interfacial friction stress. Based on the trilinear interfacial bond-slip constitutive model, the full-range debonding process for CFRP-steel interfaces was analyzed and the analytical expressions for the interfacial load-slip response, interfacial shear stress distribution, CFRP normal stress and the interfacial debonding ultimate bearing capacity were derived and verified through experiments. The results show that the proposed method can model the interfacial debonding process of CFRP-steel interfaces under the influence of temperature variation with reasonable accuracy, and that the thermal effects on the debon-ding behavior are significant and the degree of influence depends on the temperature difference and bond length.