On the basis of the real seismic data of Zipingpu reservoir from 2004 to 2007,we compared several filtering methods and choosed the ratio filtering method which can effectively filter the background noise in the seismic data without damaging the effective signal in the data. Then,wavelet transform,which has a high time-frequency resolution,was used to the denoising data of the reservoir induced earthquake and tectonic earthquake to get two kinds of seismic spectrum. After that,we extracted the time-frequency attributes from the seismic data and combined the attributes to get a new time-frequency attribute. By analyzing the time-frequency spectrum and attributes,we found the differences in time-frequency characteristics between Zipingpu reservoir induced earthquake and tectonic earthquake,which is capable of providing a basis for earthquake monitoring and analyzing.