Municipal solid waste (MSW) landfill is regarded as an important emission source of atmospheric mercury (Hg), which is associated with potential health and environmental risks, as outlined by the Minamata Convention on Hg. This review presents the current state of knowledge with regards to landfill Hg sources, Hg levels in MSW and cover soils, Hg emission to the atmosphere, available Hg biogeochemical transformations, research methods for Hg emission, and important areas for future research. In addition, strategies for controlling landfill Hg emissions are considered, including reducing the Hg load in landfill and in situ controls. These approaches mainly focus on Hg source reduction, Hg recycling programs, public education, and in situ technology such as timely soil cover, vegetation, and end-of-pipe technology for controlling Hg emission from landfill gas.