The invention relates to a traditional Chinese medicine feed additive used to improve immunity and resist parasitic infection of weaned piglets. The traditional Chinese medicine feed additive is composed of the following traditional Chinese medicine raw materials: 30-90 g of Codonopsis, 10-30 g of Atractylodes, 30-90 g of Poria cocos, 30-90 g of yam, 30-90 g of Astragalus, 10 - 30 g of lotus seed, 10-30 g of fried lentils, 10-30 g of fried barley, 10-30 g of Atractylis, 10-30 g of dried tangerine peel, 30-90 g of Polygonum, 10-30 g of Ligustrum lucidum, 10-30 g of Eclipta, 30-90 g of Epimedium, 30-90 g of Medicated Leaven, 30-90 g of melanoidin malt, 15-45 g of Rhizoma Dryoteris Crassirhizmae, 10-30 g of fried betelnut, 20-60 g of pumpkin seed, 30-90 g of dandelion, 30-90 g of purslane, 20-60 g of Isatidis and 6-18 g of licorice. The traditional Chinese medicine feed additive provided by the invention has the advantages of simple preparation process, low price and no any toxic and side effects, and can improve the immunity, prevent infectious diseases and enhance the resistance to pathogenic microorganisms and parasites of the weaned piglets, and improve the quality and yield of pig products.