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Hot dry rock (HDR) geothermal energy,almost inexhaustible green energy,was first put forward in the 1970s.Thedevelopment and testing of HDR geothermal energy are well reported in USA,Japan,UK,France and other countries orregions.In this paper,the geological characters of Yangbajing basin were first analyzed,including the continental dynamicenvironments to form HDR geothermal fields in Tibet,the tectonic characteristics of south slope of Nyainq(e)ntanglha andDangxiong-Yangbajing basin,and the in-situ stresses based on the investigations conducted,and then the site-specific miningscheme of HDR geothermal resources was proposed.For the potential development of HDR geothermal energy,a series ofexperiments were conducted on large-scale granite samples,200 mm in diameter and 400 mm in length,at high temperature andhigh triaxiai pressure for cutting fragmentation and borehole stability.For the borehole stability test,a hole of 40 mm indiameter and 400 mm in length was aforehand drilled in the prepared intact granite sample.The results indicate that the cuttingvelocity obviously increases with temperature when bit pressure is over a certain value,while the unit rock-breaking energyconsumption decreases and the rock-breaking efficiency increases with temperature at the triaxial pressure of 100 MPa.Thecritical temperature and pressure that can result in intensive damage to granite are 400-500 ℃ and 100-125 MPa,respectively.