The invention discloses a multi-color TPO vehicle interior decoration material, which sequentially comprises a polyolefin sponge layer, a multi-color TPO surface leather layer and an aqueous polyurethane coating from bottom to top, wherein the multi-color TPO surface leather layer is formed by compounding and splicing at least two mono-color TPO surface leathers, and each mono-color TPO surface leather comprises, by weight, 20-40 parts of high-density polyethylene, 20-40 parts of polypropylene, 5-10 parts of an ethylene-acrylic acid copolymer, 30-50 parts of ethylene propylene diene monomer, 15-20 parts of a tackifying resin, 0-8 parts of an inorganic filler, 2-10 parts of color masterbatch, and 1-5 parts of an auxiliary agent. The invention further discloses a preparation method of the multi-color TPO vehicle interior decoration material. According to the present invention, the multi-color TPO vehicle interior decoration material has a variety of colors, the multiple colors can be freely combined and matched, the disadvantage of the single color of the traditional TPO material is solved, and the personalized requirements of vehicle manufacturers on interior decoration materials can be met.