The invention discloses health function tea and a preparation method thereof. The health function tea comprises 41 components including astragalus, Chinese arborvitae kernel, largehead atractylodes rhizome, red sage root, Chinese yam, schisandra chinensis, chrysanthemum, gastrodia elata, jujube, poria cocos, prepared rehmannia root, white peony roots, angelica sinensis, safflower, milkwort, mulberry fruits, prepared fleece flower root, root and vine of manyprickle acanthopanax, kudzuvine root, solomonseal rhizome, wolfberry fruits, yerbadetajo herb, ligustrum lucidum, dendrobium, grosvenor momordica, black sesame, cinnamon, pulp of cornus, eucommia ulmoides, barrenwort, dodder seed, cistanche, Chinese chive seeds, gynostemma pentaphylla, black soybeans, auricularia auricular, mushroom, kelp, oriental waterplantain rhizome, green tea and honey. The preparation method comprises the steps of magnetized water preparation, raw material soaking, raw material decoction, filtering and the like. The health function tea can be used for quenching thirst, supplementing body fluid, balancing yin and yang, activating and harmonizing qi-blood and effectively reducing sub-health symptoms of energy and stress ability weakening, low immunity and the like, enables the skin to be ruddy, the facial appearance to be sleek and the hair and the beard to be black after being taken for a long time and is particularly suitable for sub-health people as well as middle-aged and aged people.