The invention provides signal processing method and system and an electronic apparatus for analysis of time-of-flight mass spectra. The method includes digitalizing an analog signal output from an ion detector to acquire complete raw time-of-flight spectra or each effective part in the raw time-of-flight spectra for a plurality of times; if the complete raw time-of-flight spectra are acquired, extracting the effective parts of each raw time-of-flight spectrum; applying a one-dimensional wavelet transform to each effective part to map to each frequency band or scale; determining positions and intensities of each spectral peak in each raw time-of-flight spectrum by detecting the maxima of an obtained wavelet coefficient distribution, and saving said peak position and intensity as characteristic data of each spectral peak; accumulating the characteristic data obtained by processing each raw time-of-flight spectrum and stacking the data to form spectral peak intensity/time-of-flight histogram.