The invention discloses a preserving agent for preserved eggs and an application method. The preserving agent is prepared from the following raw materials in parts by weight: 3-8 parts of table salt,12-20 parts of chopped green tea, 3-8 parts of fresh ginger, 25-32 parts of plant ash, 22-28 parts of bran coats, 1-5 parts of edible white vinegar, 5-10 parts of soda powder, 3-8 parts of star aniseeds, 4-8 parts of Chinese cinnamon, 3-6 parts of fennel seeds, 2-6 parts of fructus tsaoko and 3-8 parts of yellow mud. The preserving liquid has the characteristics of being free from toxin to human bodies, and good in mouth feel.