The heat convection was considered the main heat exchange type in the autoclave where CFRP pressure vessel was cured in this analysis. To determine the heat convection coefficient, it needed the combination of theoretical calculation and temperature test. In the theoretical calculation, the determination of the heat convection coefficient was considered as an inversion problem of thermal conduction. By adjusting convection coefficient value in the finite element calculation, optimization method was employed to obtain a good agreement between calculated temperature and measured temperature. In the temperature test, the metallic liner of CFRP pressure vessel was used as test component to record temperature data which was compared with the calculated temperature. The calculated results reveal that the maximum value in convection coefficient sequence is 19.87 W/m2/K; the minimum value is 0.16 W/m2/K; the maximum temperature deviation between calculation and test is 1.67 °C. The results present the equivalent thermal boundary condition for the simulation of curing process of CFRP pressure vessel.