In this paper CW diffusion chemical lasers with two energy levels are described by kinetic model. The results of the kinetic model in consideration of both inhomogenoous broadening and homogeneous broadening are given and compared with rate model. The discussion is focused on the effects of inhomogeneous broadening. The specific formulas used for the calculation of the characteristic of oscillator are given. In case of certain G, and limited chemical pumping rate K, the intensity, power output and chemical efficiency of CW chemical lasers are exactly solved.