The invention relates to a method for comprehensively recovering zinc, iron and carbon in blast furnace gas slime and belongs to the field of comprehensive utilization of secondary metallurgy resources. The method comprises the steps that the blast furnace gas slime is dried, crushed and fine ground, blast furnace gas slime powder is obtained and leached with a sulfuric acid solution, filter residues and filtrate are obtained through filtering, oxidization and neutralization are carried out on the filtrate for iron precipitation, iron residues and deironed liquid are obtained through filtering, the deironed liquid is extracted in an extraction device, and then reextraction is carried out; and electrodeposition is carried out on a zinc sulfate solution subjected to reextraction, and electric zinc is obtained. Besides, the filter residues obtained through leaching and the iron residues obtained through deironing are mixed evenly, iron concentrate powder is obtained through wet grinding and magnetic separation after magnetizing roasting under controlled proper conditions, flotation is carried out on tailings subjected to magnetic separation, and carbon in the tailings is recovered. According to the method, basically no pollutant is generated, the sulfuric acid solution and an extraction agent can be recycled, the problems of stacking of the blast furnace gas slime and heavy metal pollution are solved, environmental protection is facilitated, comprehensive utilization of resources is achieved, and the method meets the strategy of sustainable development.