Abstract: In order to realize the simulation of rough surface milling more accurate, a new micro surface topography simulation method based on wavelet hierarchical theory and wavelet energy analysis is proposed. Firstly, based on db9 wavelet basis function, the multi-scale decomposition of the measured surface topography signal of plane milling is carried out, and the main components of complex surface signal are stripped by wavelet energy analysis of layered signal. The surface topography signal of plane milling is divided into three frequency bands, namely high frequency band, theoretical frequency band and low frequency band. The high-frequency band and low-frequency band information are reconstructed into a digital combination model, and then combined with the theoretical topography obtained by milling cutter parameters and processing parameters, the topography simulation of plane milling rough surface is finally realized. Finally, the measured rough surface and the simulated surface are compared and analyzed. The results show that the maximum relative errors of arithmetic mean deviation Sa, root mean square deviation Sq, skew Ssk and kurtosis Sku are 2.568%, 2.786%, 4.785% and -2.431%, respectively. Generally speaking, the relative error between the measured surface and the simulated surface is less than 5%. This method provides a new way to realize the simulation of plane milling rough surface more accurately.