The invention discloses instant nutrient purple potato chips and a preparation method thereof. The purple potato chips are prepared from raw materials, namely purple potato whole syrup, white granulated sugar, starch, soybean protein isolate, a thickener, a compound mineral enhancer, a compound vitamin enhancer and water according to a certain mass part ratio. The preparation method comprises thefollowing steps of: A, selecting fresh and full purple potato as raw materials; B, washing and trimming, namely washing by using a washer; C, slicing and conserving color; D, heating and cooking, namely softening a tissue structure of the purple potato, treating, inactivating polyphenol oxidase and amylase which are inherent in the purple potato to protect purple potato pigments and purple potatostarch; E, beating, mixing and inflating, namely crushing heated and cooked purple potato pieces in a beater into the purple potato whole syrup; F, refining and homogenizing by using a colloid mill; G, drying and scraping slices by using a roller; H, performing secondary drying; and I, packing. The instant nutrient purple potato chips has a rational formula, wide sources of the raw materials, lowcost, excellent flavor, beautiful color, high content of the purple potato pigments and high content of nutritional ingredients, and is rapidly rehydrated and instant, and the product has a porous structure.