Abstract: The study of boundary layer inhomogeneous is of great importance in studying the characteristic of atmospheric turbulence and the applicability of the classic theory. In this paper, the development of atmosphere boundary layer is simulated in a laboratory simulation tank, and beam patterns of mixed layer are recorded. Using wavelet transform method to determine the scaling region of the power spectrum of log-intensity from beam patterns in horizontal and vertical directions, the scaling exponents can be fitted and compared with the classic value of 8/3. The result shows that the mixed layer is quite homogeneous in horizontal direction and a little inhomogeneous in vertical direction.