On the basis of the previous achievement of research on lasers in our lab the kinetic calculation of Q-switched CO2 pulse laser was completed using the CO2 laser six-temperature modeL In the calculation, the peak power of Q-switched optical pulse was obtained, the variation curves of peak generation time and pulse width vs ambient temperatures were estaoushed, and the different curves of these variables vs increasing laser frequency were worked out, which affords the grounds in theory for solving the problem caused by the working using electrooptical Q-switched CO2 pulse laser in outfield.