Novel copper-based metal–organic frameworks (Cu-MOFs) with chlorine-rich functional group were designed and used for the removal of elemental mercury (Hg0) in the flue gas. The Hg0 removal performance by the porous material was systematically studied through a series of physiochemical characterization. The results show that the designed Cu-MOFs have good crystallinity, large BET surface area, and high dispersity of constituent elements. The Cu-MOFs materials have a high Hg0 removal efficiency, with an average value higher than 90%, even in pure N2 atmosphere. The presence of O2, NO and HCl can promote the Hg0 removal efficiency. In addition, Cu-MOFs materials have also shown good resistance to SO2 and water vapor poisoning. According to the adsorption kinetics analysis, its equilibrium adsorption capacity of mercury can reach up to 123.5 mg/g. Based on a variety of characterization analyses, the removal mechanism of elemental mercury on the surface of Cu-MOFs is proposed. The results show that the whole removal process follows the Langmuir-Hinshelwood mechanism.