The invention relates to an SWRH82B high-carbon steel wire rod and a preparation method thereof, and belongs to the technical field of steel wire rods. In order to solve the problems that in an existing SWRH82B high-carbon steel wire rod production process, the number of aluminum oxide inclusions is high, the purity of molten steel is low, and the component uniformity is poor, the invention provides the SWRH82B high-carbon steel wire rod and the preparation method thereof. The preparation method comprises a primary smelting process, an LF refining process, a continuous casting process, a heating rolling process and a controlled cooling process. According to the preparation method, through production control of a primary smelting furnace, control of a refining position slag system and reasonable continuous casting process parameters, the qualified SWRH82B wire rod is finally rolled. According to the preparation method, aluminum-free deoxidation is carried out in the whole process, so that the purity of the molten steel is higher, and the obtained molten steel and a casting blank meet the requirements of the purity and the component uniformity. The preparation method has the advantages that the efficiency is high, the cost is low, the low-power segregation index of the obtained casting blank is within 1.05, the wire rod net carbon is within the second level, the martensite is less than or equal to 1.5 level, and the drawing use can be met.