The invention provides a method for producing a low leakage winding type solid electrolytic capacitor. The method comprises the following steps: step 1), cutting; and step 2), element preparation: performing formation, drying, pretreatment, monomer impregnation, oxidizer impregnation, polymerization, assembly and aging on a core package; performing formation, and immersing the core package after winding into a formation electrolyte to electrify, wherein the electrifying voltage is the withstand voltage of an anode foil, and the formation electrolyte is the aqueous solution of ammonium dihydrogen phosphate; and performing pretreatment: immersing the core package into a mending agent, drying the core package, and after that, forming a layer of insulating film which is less than or equal to 20nm on an aluminum foil surface. Compared with the previous products, the method of the invention does not require a high temperature of 230 to 300 DEG C after mending an oxide film by a formation process, thus the damage to the oxide film is less; and besides, the pretreatment is added before impregnating the monomer, an ultra-thin insulating film covering the surface of the aluminum foil can be formed, so that the defects of the oxide film can be further reduced, therefore, the leakage of solid electrolytic capacitor products produced by the invention is 20% to 50% smaller than that of ordinary products.