Abstract: The tensile damage failure mode and high-temperature thermal damage morphology of S2/430LV under the combined action of heat and force were studied from macro and micro perspectives, and the thermal properties of the materials were analyzed by DMA and TG. The failure mechanism of S2/430LV tensile specimens at 20-180℃ and the variation rule of tensile strength/modulus with temperature were revealed, and the prediction was made. The results show that with the increase of ambient temperature, the softening degree and fluidity of 430LV resin increase, and the adhesive ability between resin and fiber tow decreases. Under the combined action of heat and force, the tensile strength and modulus decrease with the increase of temperature, and both decrease most rapidly around 100℃. The failure mode of the sample also changes with the increase of temperature. Before 100℃, the failure mode shows complete fracture of the fiber, and the stress-strain curve shows significant linear elastic characteristics. But after 100℃, the failure mode changes to interlaminar delamination failure. The change of the failure mode also has a certain impact on the tensile bearing mode of the material, resulting in the tensile modulus retention rate higher than the strength retention rate, and the stress-strain curve also shows concave curve characteristics. Based on Gibson prediction model and Bisby prediction model, Origin software was used to quickly and accurately obtain the optimal values of unknown parameters of the prediction model. It is found that the fitting results of the two models are highly consistent with the experimental results.