Abstract: The temperature and cure curves of the M21C carbon fiber/epoxy composite prepreg in the advanced pultrusion process were studied. The kinetic equation of curing reaction of M21C prepreg under elevated and constant temperature was measured by DSC, which was used for the calculation of resin curing reaction. Based on the finite element software, the script combined with finite difference method and volume control method was used to solve the calculation of heat transfer and resin curing reaction, so as to obtain the temperature and cure curve, and the actual curve was measured in the production. The results show that the calculation curve is basically consistent with the measured curve, so the feasibility of the algorithm is verified. The process parameters of the advanced pultrusion (heating temperature interval and pultrusion speed) were changed and then simulation calculation was carried out. The process parameters can be optimized by calculation results. The ideal process parameters of the three-section heating in cap-beam advanced pultrusion were obtained. The ideal mold heating temperature range is 160-180-200℃. The ideal pultrusion speed is 1 cm/60 s.