The invention relates to a blast-furnace gas hydrogen chloride purifying and absorbing compound device and a method, belonging to the technical field of purifying blast-furnace gas in iron and steel plants. The device comprises an alkali liquor electromagnetic valve, an alkali liquor blind plate valve, an alkali liquor gate valve, an alkali liquor conveying and distributing pipeline, an alkali liquor nozzle, an industrial water electromagnetic valve, an industrial water blind plate valve, an industrial water gate valve, an industrial water conveying and distributing pipeline, an industrial water nozzle, a liquor-removal tower shell, an air current distribution plate, an air-liquor separation filler, an industrial reuse water electromagnetic valve, an industrial reuse water blind plate valve, an industrial reuse water gate valve, an industrial reuse water conveying and distributing pipeline, an industrial reuse water nozzle, a drainage pipeline and a drainage gate valve, which are sequentially connected through flanges. After unpurified blast-furnace gas sequentially is mixed with industrial water and alkali liquor in a spraying mode and the mechanical water drops are intercepted by a liquor-removal tower, the clean blast-furnace gas is conveyed to users, and the discharged water is conveyed to low-side uses through pipelines (19) and gate valves (20). The invention has the advantage of solving the problem that the blast-furnace gas dry type dedusting process can not prevent the hydrogen chloride component from corroding gas conduits and devices.