Abstract: Due to the unqualified copper strip corrosion test of liquefied petroleum gas (LPG) in Jinxi Petrochemical Company recently, cause analysis was conducted. Results showed that besides high hydrogen sulfide content or high sulfur content in LPG could cause the copper strip test fell, the amount of entrained liquid in LPG played an important role as well. Composition analysis, corrosion test and bubbling function of the entrained liquid and washing water were further investigated. It was found that some sulfur-containing substances, such as S2-，HS ，S2O32-，H2S and etc. in the entrained liquid could induce the unqualified copper strip test of LPG.

Key words: liquefied petroleum gas, corrosion, hydrogen sulfide, sulfur