Abstract: EEG yields non-stationary,stochastic signals.Correct representation of the fea tures of is frequencycharacteristics by enhancing the accuracy of spectral analysisextraction of phase informations as well as instantaneous wave analysis in EEG have become the hot spots of research in EEG signal processing. Principles and methods of the spectrum component parameter analysis bispectral analysis and the time-frequency analysis are here discussed Results in EEG research work are also presented.