The invention relates to a nano preservative film for preventing edible fungus from deterioration and application thereof, and a preparation method and application thereof, belonging to the technical field of agricultural product storage processing. The preparation method comprises the following steps: taking 15 wt% of nano powder (30% of nano silver, 35% of nano titanium dioxide, 25% of nano attapulgite and 10% of nano silicon dioxide), 45 wt% of low density polyethylene, 22 wt% of low density linear polyethylene, 10 wt% of dispersing agent, 5 wt% of lubricant and 2 wt% of coupling agent, evenly mixing, extruding, cooling and carrying out set cutting to obtain a nano master batch; and taking 7.5 wt% of nano master batch, 8 wt% of antifogging agent master batch and 84.5 wt% of low density linear polyethylene, carrying out hot melt, evenly mixing, and running to form the nano preservative film with the thickness of 18 mu m. The nano preservative film is used for packaging edible fungus to form a high-humidity low-oxygen environment; the lower spoilage microorganism activity and ethylene content can effectively inhibit the after growth, deterioration and other phenomena of the edible fungus, effectively maintain the storage quality and enhance the commodity value of the edible fungus; and thus, the nano preservative film has wide market prospects.