Simulation of inlet distortion is carried out by using a method of the Insert board to test the stability of inlet／engine matching work of a domestic engine, and five operation states, i.e., nlcor=70％, 75％, 82％, 89％, 96.7％ are selected. The numerical simulation results and the test results of steady total pressure distortion and Δσ0 of the inlet are contrasted and analyzed. The steady total pressure distortion obtained by calculation is the same as that obtained by test. When nlcoris constant,Δσ0is non-linear with the change of the height of the insert board. When the height of the board is above 30％, Δσ0 begins to soar. When the height is constant,Δσ0 is non-linear with the change of nlcor. nlcor changes dramatically at value 82％.