Hot dry rock geothermal resource is a new type of renewable green energy with large reserves and potentially wide applications that should be better investigated and evaluated. This paper systematically summarizes and analyzes the key technologies involved in the investigation and evaluation of dry hot rock geothermal resources from the perspective of site selection, geophysical exploration, drilling, core sampling test, comprehensive logging, pumping and water injection test, target layer fracturing and thermal reservoir evaluation. At the same time, the GRY1 hole in Lijin, with poor natural fracture rate and permeability, is used to explain how its permeability coefficient has been greatly improved after hydraulic fracturing. The fracturing mode belongs to the artificial high pressure+natural fracture composite fracturing mode, which can obtain a large amount of injected water under the controllable orifice pressure, which is conducive to the development and utilization of hot dry rock resources. During the fracturing test of the hot dry rock, the development section of the natural hot fracture should be selected as the target layer of the fracturing test. In the Chenzhuang Latent uplift, the thermal resources of hot dry rock within 5000 m depth are 2. 654×10↑20 J, equivalent to 9. 021 billion tons of standard coal. The available resources are 5. 29×10↑18 J, equivalent to 180. 4 million tons of standard coal. This study has significance for guiding site selection, investigation and evaluation of hot dry rock exploration and development project.