Abstract: The radiation crosslinking modification of 30wt% glass fibers (GF) reinforced nylon 6 (PA6) composites was conducted using electron beam at different radiation doses. The triallyl isocyanurate (TAIC) was used as the sensitizer. The effects of radiation doses and sensitizer loadings on the structure, mechanical properties, water absorption and thermal stability of GF/PA6 composites were investigated. The experiment results show that the tensile strength, flexural strength, and impact strength of GF/PA6 composites are enhanced by 15.7%, 43.2%, 18.7% and 17.3%, respectively, at a TAIC content of 1wt% and a radiation dose of 50 kGy. Moreover, both the crosslinking structure of the GF/PA6 composites composites and the carbonized structure after the pyrolysis are observed by SEM. The crosslinking density of GF/PA6 is found to increase with increasing the radiation dose. During the pyrolysis process, the formed dense carbonized structure is effective in slowing down, even eliminating the formation rate of molten drops of GF/PA6 composites.