The bichromatic waves propagation into a narrow-long harbor excites low-frequency oscillations inside the harbor,and the influence of wave secondary reflection on the wave maker is reduced due to reasonable arrangement of physical model experiment.Concurrently,reasonable experiment layout reduces the influence of wave re-reflection on wave maker.Fast Fourier transform and wavelet transform are adopted to investigate the amplitude-frequency response of different bichromatic waves and the distribution of wave energy in time-frequency domain.The non-linear interaction process between different components of waves is also investigated by employing the wavelet-based bispectrum. The results show that:when the short wave of bichromatic waves has different resonance frequencies corresponding to the harbor,the sub-harmonic frequency wave amplitudes generated by wave nonlinearity are different in the harbor;when the short wave of bichromatic waves corresponds to the lower resonance frequencies of the harbor,the waves would gather more energy in the harbor;the non-linear transfer processes of wave energy are revealed between sub-harmonic frequencies and superharmonic frequencies in wave components and the short wave frequency.