The invention discloses a method for extracting potassium chloride from sintering dust in iron and steel enterprises. The method comprises the following steps: fully stirring a leaching solution and sintering dust under normal temperature and normal pressure conditions for 0.5-1 hour, conveying the formed slurry to a mechanical filter pressing unit after completion of leaching, performing solid-liquid separation on the slurry through the mechanical filter pressing unit, drying the leaching residues, returning to a sintering process, leaching the leaching solution again, allowing the leaching solution to enter a membrane process impurity removal unit, conveying the leaching solution to a quartz sand filter through a pump, filtering to remove particles in the liquid, performing micro-filtration treatment, and removing colloid in the liquid; finally, realizing separation of multivalent metallic impurities and potassium through nanofiltration, so as to obtain a refined potassium-containing pregnant solution, allowing the refined potassium-containing pregnant solution to enter a membrane distillation and crystallization unit, concentrating the potassium-containing pregnant solution by utilizing a low-temperature heat source of the iron and steel enterprises, cooling, so as to obtain a potassium chloride crystal. The method disclosed by the invention is simple in process, high in degree of automation and low in energy consumption, wastewater emission is avoided, and comprehensive utilization of harmful solid wastes in the iron and steel enterprises is realized.