Japan Atomic Energy Research Institute (JAERI) and the Institute of Physical and Chemical Research (RIKEN) are going to build an 8 GeV synchrotron radiation source in Harima Science Garden City, 100 km west of Osaka. The facility consists of an 8 GeV storage ring of 1436 m circumference with a natural emittance of 6.9 nmrad, an injector linac of 1 GeV and an 8 GeV synchrotron. Construction stars in 1990 and the first beam is foreseen in 1998. At the commissioning time 10 beamlines will be available. The remaining 50 beamlines, 32 on insertion devices and 18 on bending magnets, will be constructed successively.