Abstract: This paper presents a method of sound spectral analysis and display which is as convenient and objective as the sound spectrograph and the oscilloscope in the laboratory and it can be used for the multippurpose research of speech and other similar signal with the help of computers. This method implements the analysis of signal spectra and waveforms using the graphic display by means of man-machine communications. Beside the time waveforms, it can display three types of the dynamic power spectrogram, i.e. brightness modulation picture, perspective drawing and isogram. The generated spectrogram can futher be dissected into sections and analysed quantitatively. It will allow users to designate freely 15 kinds of parameters.