Hot dry rock， a strategic clean energy resource， belongs to the category of solid minerals， and its occurrence conditions are controlled by the geological environment. With the execution of the hot dry rock resource survey project in Henan Province， and the comprehensive study of hot dry rock reservoir-forming characteristics and drilling results at home and abroad， it is inferred that the heat source of hot dry rock is mainly composed of two modes： the heat transfer of intrusive rock mass and the heat transfer of mantle （convective heat transfer of deep buried faults）. The reservoir-forming environment must have three basic conditions： huge and stable high thermal conductivity rock mass， thick and stable low thermal conductivity overburden and heat source. In view of the existing problems in the prospecting theory and drilling for hot dry rock resources， the preliminary prospecting direction and suggestions are put forward.