Abstract: Mercury catalytic oxidation technologies in recent studies are summarized in this study tohighlight the present research development and future perspective of catalysts. The mercury oxidationcatalysts are classified into V-based catalyst, noble metal catalyst and transition metal oxides catalyst.The mercury oxidation efficiency (MOE) of V-based catalyst strongly depends on HCl and Cl2 concen⁃trations in the flue gas. The noble metal catalyst (e.g., Au, Ag, Pt, Ru and Pd-based) is a promisingmercury oxidation catalyst because of its strong affinity toward mercury atom. The transition metal oxides(Cu, Mn, Fe, Mo, Ag, Pd, Cr, etc.) has also been used to develop low and middle temperature cat⁃alysts for Hg0 oxidation. Most of these catalysts have very high mercury oxidation efficiencies at acertain temperature, but NH3 and SO2 in the flue gas seriously suppress the catalyst activity from 94.7%±3.9% and 83.9%±4.8% to 66.8%±16.8% and 57.1%±7.5%, respectively. It is concluded that puremetal oxides serving as single oxidation site would not be suitable mercury oxidation catalysts in thecomplex flue gas environment. The multicomponent metallic oxide catalysts generate more species oxi⁃dation reaction sites for NO reduction and Hg0, which promotes the possibility of NO and Hg0 synergicremoval. This work also proposes the future challenge of highly efficient Hg0 oxidation catalyst.