The invention discloses a food-level tea saponin dish-washing liquid containing oxidized tea polyphenol. The food-level tea saponin dish-washing liquid is prepared from the following components in percentage by weight: 15% to 30% of tea saponin, 0.1% to 1% of oxidized tea polyphenol, 0.1% to 1% of sodium alginate, 0.1% to 1% of sodium polyacrylate, 0.1% to 0.5% of nisin, 0.1% to 0.5% of sodium dehydroacetate, and the balance of water, wherein the weight percentage uses the total weight of dish-washing liquid as basis, and the sum of percentages of components by weight is 100%. The food-level tea saponin dish-washing liquid has the advantages that natural plant dish-washing liquid is realized, the oil dirt removal ability is strong, the foam content is low, the bleaching is easy, the environment-friendly effect is realized, the preparation technology is simple, and the industrialized production is realized.