Hydrogen sulfide (H 2 S) in landfill gas, formed with the biodegradation of municipal solid waste, is a major odorous component in a landfill. It poses a potential risk to humans and causes odor problems and complaints by the residents near landfills. Many studies have been conducted on landfill gas qualities. Also, various H 2 S control technologies have been used in different industrial sectors. However, comprehensive reviews on H 2 S issues in landfill gas are rare. An understanding of the formation of H 2 S encountered in landfill gas and the emission at which it occurs helps assess risk and problems. The authors review recent publications from different perspectives on H 2 S odor in landfills, including H 2 S generation the impact on the environment and human health, H 2 S levels in the landfill environment, and H 2 S control technologies at landfills.