To investigate the unsteady flow characteristics of the low-pressure turbine suction surface boundary layer of an aero-engine under the influence of wake,the commercial software CFX 15.0 was used for numerical simulation in this paper,and a cascade test platform with an upstream wake simulation function was used for experimental veri-fication.Firstly,three different upstream reduced frequencies of wakes were achieved by changing the speed of the upstream wake bar while keeping the axial velocity unchanged.Then,by numerical simulation,the flow field data of the low-pressure turbine suction surface boundary layer under three conditions were obtained and compared.Three new flow field analysis methods including proper orthogonal decomposition(POD),dynamic mode decompo-sition(DMD)and Fourier mode decomposition(FMD),were used in the analysis.The results show that,under the three reduced frequencies,the height of the wake center from the blade surface differs greatly when it passes through the separation area.The influence degree of the wake in the suction surface boundary layer and the main identified characteristics are also very different under the influence of wake.