Abstract: By comparing the modeled results with observations obtained by Wuhan University Lidar, the validity of the current Na layer model is examined. With a small number of permitted adjustable parameters, the model is able to reproduce many observed features of the Na layer remarkably well. The stability of a simplified model is analyzed by using the perturbation method. It is indicated that the model is a stable system because all the model’s five eigenvalues’ real parts are negative when reasonably adjusting the mayor coefficients, including the wavelengths of perturbations, the concentration of the background chemical species, eddy coefficient, and temperature. The results show that the wavelengths of perturbations and the magnitude of eddy coefficient strongly influence all the five eigenvalues: the magnitudes of all the eigenvalues’ real parts ascend with the increasing perturbation wavelengths and descend with the increasing eddy coefficient. However, the concentrations of the background clemical species and temperature have strong effects on only part of them.