The invention relates to a double layer wine-storing tank, which includes an accessed nitrogen flushing system; the wine-storing tank is composed of two tanks with one superposes on the other, the volume of the upper wine-storing tank is larger than that of the lower wine-storing tank, and reinforcing structure is arranged between the two wine-storing tanks; the upper wine-storing tank and the lower wine-storing tank are respectively provided with an upper tank nitrogen-flushing pipeline and a lower tank nitrogen-flushing pipeline which have the pipeline function of charging and discharging nitrogen and the function of cleaning the tank; the nitrogen-flushing pipeline at the top of the upper wine-storing tank has a backflow prevention device used for preventing the wine flowing back to the pipeline so as to cause the bacterial infection; the upper tank and the lower tank respectively have an upper cooling honeycomb panel and a lower cooling honeycomb panel to increase the rigidity of the wine-storing tank. The invention has the advantages that the double layer wine fermentation tank can meet the technique requirement for the production of high-quality red wine, thus filling the domestic blankness; the using area of the workshop can be saved; the rigidity and stability of the wine tank can be guaranteed; the invention is convenient for the worker to operate and disassemble.