The invention discloses a preparation method of preserved plums. The preparation method is characterized in that the preparation method comprises the following steps: (1), salting: scratching seams in Nai plums, adding 15 percent of salt, selecting hard and green Nai plums and salting for half a year; (2), desalinating: desalinating the Nai plums until 4 percent of salt content is retained; (3), preparing ingredients of fructus anisi stellati, cinnamon, white sugar, salts and citric acid; (4), boiling water: boiling the ingredients with water; (5), drying the Nai plums in the sun, and allowing exposiure in the sun or bakeout until the water content of the Nai plums is 70 to 80 percent; (6), pickling: pickling the Nai plums into hot spice water, soaking in a hot state for at least one day and one night or above, putting the Nai plums in a refrigerator in summer and putting the Nai plums in a room in winter; (7), repeating the steps (4), (5) and (6), fishing out the plums, and continuously boiling with water; enabling the material to be diluted by absorbing one part of material, decocting for enabling the material to be thicker by losing part of water, then drying the plums in the sun until the water content reaches 70 to 80 percent, soaking in the hot state, and repeating the steps for 3 to 4 times until spice is completely absorbed; (8), drying, wrapping a layer of licorice powder or white sugar powder, then sieving the powder and finally obtaining a maroon finished product. The preserved plums prepared by adopting the preparation method disclosed by the invention are delicious and sweet in taste, and have the efficacy of relieving summer heat and relieving fatigue.