Abstract: The perturbation power spectrums of dust density and electron density at different altitudes in the summer polar mesopause are calculated based on the data of ECT-02 experiment in this paper. Fourier analysis method is applied and the numerical results show that the perturbation power spectrum indices of the dust plasma at different altitudes are quite different. Based on the analysis of the power spectrum, it is proved that the irregular plasma structure at mesopause region is not always generated by neutral atmospheric turbulence, which is consistent with experimental observation results. The results obtained in this paper are of great significance for understanding the physical mechanism of polar mesosphere summer echoes (PMSE).