To explore the deterioration mechanism of the bonding performance of Embedded Through-Section (ETS) Glass Fiber Reinforced Plastic (GFRP) bar-concrete interface in high-temperature environments, and based on the Fiber Reinforced Polymer (FRP) bar technology, 108 pull-out specimens were designed and prepared in this study. The test variables included three key parameters: temperature (20,40,60,80,120 and 160 ℃), concrete strength grade (C30, C40 and C50) and GFRP bar diameter (8, 12 and 16 mm). The test showed that when the temperature reached the glass transition temperature (T_g) of the adhesive, the failure mode of the specimens changed significantly, and the splitting failure of the concrete matrix evolved into interfacial debonding failure. Under the interfacial debonding failure mode, the typical bond-slip curve could be divided into three characteristic stages: linear rising stage, softening stage and residual strength stage. Based on the theory of fracture mechanics and the regression analysis of experimental data, a calculation model of the correlations of bond strength, residual bond strength and fracture energy with temperature parameters was established. The results showed that the increase of temperature had a significant deteriorating effect on the interfacial bonding performance, especially when it was close to the adhesive's T_g, the bond strength showed an exponential decay trend. Compared with the experimental data, the prediction error of this model was within 10%, and the model has high engineering applicability.