Abstract: Although there are abundant geothermal resources in Rucheng, Hunan, research on Hot Dry Rock (HDR) geothermal resources is still in its early stages. In order to learn more about the geothermal characteristics and resource potential of HDR in the Rucheng area, this paper analyzes the geothermal occurrence conditions of HDR in this area using a field geological survey, sampling test, and geothermal resource genesis analysis. According to the site selection standard of the HDR exploration target area in China, the HDR target area in the area is evaluated, and the volume method is employed to estimate the amount of HDR resources. The research indicates that the Rucheng area has a well-developed intermediate-acid magmatic rock mass with a good geothermal geological background. The heat generation rate of granite is 6.45 μW/m³, which makes it a highly radioactive granite. It belongs to the 'hot crust and cold mantle' thermal structure type and is rated as the suitable area for the target area of HDR resources. At a depth of 2~6 km, the total amount of HDR resources is 13.06 × 10¹⁷ kilocalories, equivalent to 445.60×10⁸ tons of standard coal, with good resource potential. This study provides a scientific basis and technical support for the development of HDR geothermal resources in the Rucheng area, lays the foundation for the sustainable utilization of geothermal energy, and has good guiding significance.