Abstract: The cleaning technology for the raw gas is one of the key obstacles restraining the development of gasification technology.During the gasification process,parts of sulfur,nitrogen and volatile heavy metal in coal would transfer to gaseous phase together with the gasification products,which further affect the following usage of gas.Thus,it is necessary to remove the components effectively,especially the simple substance of mercury from the coal derived gas.Introduce the current technologies for Hg capture,and the active carbon supported sulfur,metal oxides and noble metal sorbents.Besides,the main challenges of Hg capture and its development direction are also analyzed.The adsorption of Hg with active carbon is well studied,however,its high cost and low working temperature（≤150 ℃） are the main defects.Below 150 ℃,the ferric oxide is a represent of metal oxides performing high desulfurization and Hg capture ability,simultaneously the noble sorbents has great potential for Hg removal between 200 ℃ and 350 ℃.Furthermore,it has a sulfur tolerance to some extent.The combination of removal of Hg and other pollutants（sulfur,chlorine,etc.） has good application prospect.