The invention belongs to the field of environmental engineering, and in particular relates to a device and a method for comprehensively treating acidic sulfate organic waste water based on biological desulfurization. The method comprises the following steps of: 1, reducing sulfate in the organic waste water, blowing hydrogen sulfide off, namely (1-1) mixing the acidic sulfate organic waste water and sulfide-containing recirculation water in an anaerobic digestion reactor, controlling the pH of the mixture to be 5.0 to 6.0, and thus obtaining a hydrogen sulfide-containing acidic mixed solution, and (1-2) introducing inert gas, blowing the hydrogen sulfide off, adding sulfate reducing bacteria, reducing the sulfate to form sulfide, obtaining the sulfide-containing recirculation water and returning to the step (1-1); and 2, absorbing, oxidizing and recycling the hydrogen sulfide, namely (2-1) absorbing the hydrogen sulfide blown off in the step (1-2) by using a weak alkaline solution, adding sulfur-oxidizing bacteria, oxidizing the hydrogen sulfide to form elemental sulfur, separating to obtain the elemental sulfur and effluent, and (2-2) treating the effluent for recycling. By the device and the method, sulfate innocent treatment and resource recovery treatment are realized.