Objective: To compare chemical constituents in Halitum Violaceum before and after processed by vinegarand explore its material basis of processing attenuated. Method: Silver nitrate titration method

ultraviolet spectrophotometric method

methylene blue spectrophotometric method

microwave digestioncombined ICP-AES method and indicator discoloration were adopted to compare contents of NaCl

sulphur

sulfide

trace elements before and after being processed by vinegar and odour gas escaped during processing course. Result: The content of NaCl were both higher than 85% in crudeand vinegar processed Halitum Violaceum which was slightly higher after being processed;the mass fraction of sulphur in crudeand vinegar processed Halite Violaceous were 87.75-144.56 and 19.21-28.54 μg·g-1

respectively;the mass fraction of sulfide were between 0.045%-0.061% in different batches of crudeprocessed Halitum Violaceum and no sulfide was detected in vinegar processed Halitum Violaceum. Harmful elements of As

Cd

Cr and Pb were reduced after being processed;odour gas escaped during processing coursewas hydrogen sulfide. Conclusion: Halitum Violaceumwas purified after being processed by vinegar

potential toxic ingredients were removed and chemical constituents were changed greatly.This study could provide a reference for material basis of processing attenuated mechanism of Halitum Violaceum.