Hot dry rock (HDR) geothermal energy, which utilizes the natural heat contained in low permeable rock mass, could be estimated to provide a great amount of energy for electricity. NEDO has been concentrating research efforts on developing HDR geothermal energy from 1985 under a renewable energy development program, named the Sunshine project. Required technology for developing HDR energy is summa-rized in this paper.This report will also focus on the results obtained in 1989 as well as a brief histry of the Hijiori project and recent R&D situation in America and Europe.