The utility model discloses a flue gas desulfurization industry test device of multi -functional tower technique relates to a flue gas desulfurization industry test device, including the absorption tower system to and with the absorption tower headtotail and supply with the absorbent feed system of absorbent, the absorption tower system includes the fixed subassembly of lower part and the detachable assembly on upper portion, and fixed subassembly includes that the absorption tower bottom cell body of lower part and the flue gas on upper portion enter the mouth, and detachable assembly is absorption tower tower -type structure subassembly the flue gas absorbing district of lower part and the fume emission flue on upper portion, fixed subassembly and detachable assembly can dismantle the connection. The utility model relates to a do small investment, fixed, place occupy little, as can to dismantle equipment collection lime stone the industry test device of the multi -functional tower technique of wet flue gas desulfurization such as gypsum wet desulphurization, seawater desulfurization technology.