The invention provides a spectral peak prominence index-based spectral peak number identification method. The spectral peak prominence index of the discrete spectrum of data signals is calculated, so that the number of prominent spectral lines in the discrete spectrum of the data signals is obtained. The spectral peak prominence index-based spectral peak number identification method avoids complex calculation in the artificial search of the number of the prominent spectral lines of the data signals and a prominent spectral line judgement threshold, the range of spectral peaks can be determined as long as the number of the spectral peaks is known, the efficiency of spectral peak identification is increased, and spectral peak identification is more intelligentized.