Abstract: In order to study the influence of hot and humid acid rain environment on the shear bond performance of carbon fiber reinforced polymer (CFRP)-concrete interface, 45 CFRP concrete single shear specimens were designed and manufactured. The hot and humid environment was simulated by mechanical high temperature dry and wet cycles and manually configured acid rain solution with pH 1.5. Through CFRP concrete shear tests, the effects of concrete strength and corrosion times on the interface failure mode, peel bearing capacity, ultimate displacement, load displacement curve and strain distribution in the bonding zone were discussed, an interfacial constitutive model based on the influence coefficient of hot and humid acid rain was established, and the reference method for the division of corrosion degree in hot and humid acid rain environment was proposed. The results show that with the increase of concrete strength, the interface bonding performance is enhanced, and the interface peeling position gradually changes to the adhesive layer. With the increase of corrosion times, the interfacial bonding performance presents a trend of increasing first and then decreasing. The corresponding interfacial peel bearing load and ultimate displacement of the three strength concretes are 3.04%, 3.50%, 5.78% and 0.50%, 0.49%, 0.95% higher than those of the uncorroded specimens, respectively. SO₄ ^2– ions in acid rain invade the concrete surface to generate expansive material CaSO₄·2H₂O, which will temporarily enhance the interfacial bonding performance in the early stage of corrosion. In the tangential shear test, the load displacement curve presents four stages: Rising, concussion, strengthening and falling. The direction of stress transfer in the bonding zone is from the loading end to the free end. The interfacial constitutive model of the influence coefficient of hot and humid acid rain proposed in this paper is in good agreement with the existing test data, with high accuracy and safety. The related research results can provide theoretical support and design guidance for CFRP reinforcement project in high humidity and high heat acid rain area.