We introduce the wavelet transform for phase reconstruction of SPIDER in this pa per. With the technique, we can directly read the phase from the wavelet transfo rm of spectral interferogram, which essentially eliminates the phase noise resul ting from improper temporal filters in the conventional Fourier method. The simu lation and the practical example proved the validity and reliability of this tec hnique. This technique will find more applications in generation and characteriz ation of monocycle optical pulses.