Due to the extremely weak underwater vibration characteristics, with the water surface information detected through laser coherence method, it is a hard work to obtain the underwater vibration characteristics from the water surface information by using traditional spectral analysis. Therefore, on the basis of the traditional spectrum analysis, the underwater vibration characteristics obtained from water surface information can be enhanced effectively with short-time Fourier transform (STFT) and wavelet multi-scale transform. Through analyzing the vibration experiment of a vibration source with 1 000 Hz placed underwater 80 cm, the results show that the underwater vibration characteristics are enhanced, which is useful to extract the target characteristics.