Abstract: On the occasions that classical methods of mute-noise based on the Fourier analysis are disable to deal with ateruatio cunves of Transient Electromagnetic Method, the application of wavelet analysis on the abstraction of TEM signal can separate the useful signal from noise effectively and make the result close to the true value to obtain a content result, by using the wavelet Sym6 as the parent function, using the Mallat algorithm to decompose the primary TEM signal, using different threshold values to rebuild signals.