T700/TDE-86 carbon fiber reinforced composites were subjected to artificial accelerated hygrothermal aging experiments.By comparing and analyzing the cross-sectional morphology and physical and chemical properties of the composite before and after aging，the moisture absorption and diffusion behavior of the composites were discussed， and the evolution law of the mechanical properties of composites was studied. The residual strength calculation model was constructed， and aging life of the composite in the hygrothermal environment was predicted by combining with the environmental coefficient. The results showed that the moisture absorption rate of the composite gradually increased until it turned flat with prolongation of aging time， which conformed to Fick''s diffusion law. Compared with composite without the hygrothermal aging， the mechanical properties of aged composite decreased under 60℃ and 95%RH， among which the shear strength was the most serious， up to 25% after 64 days of aging.The life of T700/TDE-86 carbon fiber reinforced composites estimated based on residual strength and environmental coefficients was about 30 years， laying a foundation for determining the future service reliability of resin-based composites.