Abstract: Long glass fiber reinforced nylon10T(LGF/PA10T) composites were prepared by melt blending method, and the effects of different thermal-oxidative aging time on the static and dynamic mechanical properties of LGF/PA10T composites were characterized by DSC, DMA, SEM and mechanical properties test, and the activation energy of glass transition of LGF/PA10T composites were calculated. The results indicate that PA10T molecular chains are a little cross-linked in the initial stage of aging, slightly increasing the rigid properties of material, but the molecular chains fracture and the reduction of molecular weight play a vital role in the whole aging process. After aging at 240℃ for 50 d, the tensile strength retention rate, flexural strength retention rate and notch impact strength retention rate of LGF/PA10T composites are 4.9%, 6.3% and 9.4%, respectively. With the increase of aging time, the interfacial interaction between glass fiber and PA10T matrix is weakened, both of the glass transition temperature and damping capacity decrease. The calculation results of activation energy show that thermal-oxidative aging can make the mobility of PA10T molecular chain changed and reduce the thermal stability of LGF/PA10T composites.