This paper give a new approach to suppress noise in scismic data According to the time-frequency local characteristics of wavelet transform and the optimal filtering characteristics of KL transform, we have advanced this approach. On the basis of the fact that the noise energy is different from reflection energy in each frequency range. prestack seismic data is divided into different frequency band by wavelet transform firstly, and then is Filtered by KL transform. Synthetic and real data processing results show that the method can desirably eliminate noise.