A mathematical model for extraction of red pepper seed oil with supercritical CO2 was proposed. Some factors influencing the process were investigated, including operation pressure, temperature and extraction yield X-e (%). The model was solved by the method of weighted residuals and used to simulate the process numerically. The kinetic equation is expressed as X-e = -16.8606exp(-t/9.98177) + 16.95457 and the simulation results are in excellent agreement with the experimental data. The optimal operating parameters are 30 MPa, 318 K and 60 min.