Abstract: Based on the wave data at south pat of radial sand ridges,the measured wave envelope spectrum was computed by using the envelope theory.Besides,an improved formula was utilized to fit the normalized average wave envelope spectrum and an empirical wave envelope spectrum that reflectsthe energy distribution of wind waveat south part of radial sand ridges was obtained.Meanwhile,wave group height and group length were both consid-ered and more reasonable parameter value suitable for this area werere commended.In addition,the formula of the empirical wave envelope spectrum of wind wave was simplified by substituting the relevant statistical parameters intothe fommula.The value of spectral peakand zeroth moment of empinical envelope specta was compared with the measured envelope spectra.The results show that the ranges of relative ermorwere 0.1%～80.0%and 0.0%～23.5%,respectively,and the averagevalue was 23.5%and 5.0%,respectively.Overall,the empirical wave en-velope spectra were coincided well to the measured wave spectra and this studyshould providecertain reference for the wave group theoretical research and engineering construction in the future.