Peptides in crude venom from male Lycosa sinensis were isolated by means of reversed–phase high–performance liquid chromatography, and their relative mass in eluted fractions were analyzed through MALDI– TOF–TOF mass spectrometry. In total, 195 peptides were detected out with the relative mass ranged from 1 000 to 10 000. The vast majority of these peptide mass fell in the ranges of 1 000–3 500 and 4 500–7 500, respectively. Its molecular weight distribution was far dissimilar from those of other spiders reported, which is probably because venom components might vary with spider species.