Abstract: A method of removing mercury from a mercury-containing flue gas, especially flue gas from a refuse incinerator, is provided. The mercury-containing flue gas may also contain dust, further heavy metals, and further gaseous noxious gas components. The mercury, using an alkali sulfide solution, especially sodium sulfide solution, and in particular sodium tetrasulfide solution, is converted to mercury sulfide and the mercury sulfide is precipitated out via a dust separator. The alkali sulfide solution is introduced into the flue gas accompanied by the simultaneous addition of heat.