In Lamb wave d amage imaging of complicated aircraft structures, the signal wave packets can be easily elongated and deformed due to the dispersion of Lamb wave. The signal resolution is then degraded and the final damage imaging results could be affected . Lamb wave dispersion compensation has become an issue needing to be resolved immediately. However, the traditional dispersion compensation methods usually require the theoretically-calculated dispersion curves of Lamb waves and are hard to be applied in complicated aircraft structures. In this paper, with in-situ measured relative wavenumber curves, the compensation process of linearly-dispersive signal construction (LDSC) is performed to solve the difficult problem of dispersion removal of Lamb waves in complicated aircraft structures. Hereafter, LDSC is used in delay-and-sum imaging to realize high resolution damage imaging, during which the quasi-wideband excitation waveform of 1.5-cycle sine burst is introduced to reduce the influence of complicated aircraft structures. Finally, the proposed methods are verified by the experiment on the actual complicated aircraft beam.