The invention relates to black tartary buckwheat tea with effects of maintaining beauty and keeping young and a preparation method thereof. The black tartary buckwheat tea with effects of maintaining beauty and keeping young is prepared by mixing and processing 98-99 weight parts of basic tea and 1-2 weight parts of health tea, wherein the basic tea is prepared by processing the following raw materials in parts by weight: 60-80 parts of black tartary buckwheat, 10-30 parts of oat, 10-15 parts of burdock, 10-20 parts of red dates, 8-10 parts of semen sesami nigrum, 10-20 parts of walnuts, 10-20 parts of rose flower, 5-15 parts of arabian jasmine flower, 5-10 parts of lucid ganoderma, 10-15 parts of Angelica sinensis, 10-15 parts of longan and 10-20 parts of glutathione; and the health tea is prepared by processing the following raw materials in parts by weight: 5-7 parts of radix bupleuri, 11-13 parts of raw Chinese herbaceous peony, 12-18 parts of rhizoma phragmitis, 14-16 parts of the root bark of white mulberry, 12-18 parts of dandelion, 10-14 parts of radix polygonati officinalis, 15-25 parts of rhizoma smilacis glabrae, 8-15 parts of fried moutan bark, 10-20 parts of herba epimedii, 8-15 parts of rhizoma cyperi with vinegar, 10-15 parts of dried rehamnnia root, 4-8 parts of liquorice, 4-8 parts of cicada slough, 10-15 parts of radix curcumae, 8-15 parts of raw bighead atractylodes rhizome, 4-10 parts of dried tangerine or orange peel, 8-15 parts of fried radix scutellariae, 5-10 parts of plum blossom, 20-35 parts of vine of multiflower knotweed and 10-20 parts of cortex dictamni. The black tartary buckwheat tea disclosed by the invention can be used for supplementing nutrition, relieving mental stress, maintaining beauty and keeping young.