The purification of the impurity containing in acetylene gas is of important re- lation relation to not only its purity but also the quality of the welded workpiece and thecut materials as well as the safety of the operator. Therefore,this problem should be con- sidered and solved properly.The systematic analysis and comparison of dry and wet pro-cesses used for the acelylene gas purification are made. The results have shown that thewet process has advantages of good purification tlualtity,safety and reliability etc,It pro- vides a hasis for replacing the dry process.