The invention discloses an organic/inorganic ultrafiltration membrane prepared by dissolving ginger stem and doping active carbon and a method thereof, and relates to the technical field of ultrafiltration membrane preparation. The method comprises the following steps: adding pretreated ginger stem into an anhydrous lithium chloride/N,N-dimethylacetamide solution to dissolve the ginger stem at 150-160 DEG C to obtain a uniform transparent solution, adding active carbon powder and fully dispersing to obtain a cast coating liquid, defoaming, heating the cast coating liquid to 90-100 DEG C, and knifing so as to obtain the organic/inorganic ultrafiltration membrane. Mass ratio of anhydrous lithium chloride to N,N-dimethylacetamide is 1:8-1:100. The composite membrane prepared by the above method has adsorptive property and has a certain antibacterial property. According to the invention, the problem that discarded juiced ginger stem will pollute the environment is solved.