Abstract: The reaction kinetics of MC nylon 6 and MC nylon 6/ Kevlar fiber composites was obtained by differential equations of nonisothermal kinetics and modified by considering the temperature field. The reaction activation energy of MC nylon 6 and MC nylon 6/ Kevlar fiber composites changed from 90.3 kJ·mol^-1 and 102.4 kJ·mol^-1 to 72.9 kJ·mol^-1 and 80.1 kJ·mol^-1 after modified, the frequency factor changed from 1.76×10⁹ and 4.02×10¹⁰ to 1.26×10⁷ and 9.18×10⁷ accordingly, both of the treating activation energy and frequency factor were closer to the real system. KF could increase the value of activation energy and frequency factor for MC nylon 6. The reaction orders of MC nylon 6 and MC nylon 6/ Kevlar fiber composites are approximately first-class.