1956 Nov. The Preparatory Committee for the founding of a research reactor was organized with Prof. Hideki Yukawa as the first chair.
1958 Sep. The Kansai Committee was formed.
1960 Dec. Kumatori in Osaka was chosen to be the location.
Head office was formed in Kyoto University Engineering Laboratory (now Institute of Advanced Energy).
1961 Sep. Application for the foundation was filed.
1962 Mar. The application was accepted.
1963 Apr. The Research Reactor Institute was established as an Inter-University Research Institute and started as a Joint Research Institute. (Administration Office, Research Reactor, Workshop, Tracer Laboratory, Research Building, Waste Management Facilities and Guest House were completed. Further, six research divisions; Reactor Physics and Engineering, Reactor Facilities, Hot Laboratory Facilities, Scientific Instrument, Waste Management Facilities and Radiation Monitoring System were formed.) Prof. Kiichi Kimura became the first director.
1964 Mar. The Neutron Generator Room was completed.
June. The Research Reactor reached the critical stage.
Aug. A nominal maximum power of 1000kW was achieved.
1965 Jan. Joint research started.
1968 July. The nominal maximum power was increased to 5000kW.
1969 Mar. The Gamma-Ray Irradiation Laboratory was constructed.
Apr. The Reactor Thermal Properties Management Division was established.
1974 Mar. KUCA (Kyoto University Critical Assembly) was constructed.
Aug. KUCA reached the critical stage.
1975 Apr. The Reactor Utilization Center was opened.
1976 Apr. The Radiation Physics Division and Reactor Nuclear Properties Division were established.
May. The Radiation Oncology Research Laboratory was constructed.
1977 Apr. The Technical Staff Office was established.
Nuclear Biology Division, Nuclear and Radiation Physics Division, Reactor Physics Division, Slow Neutron Physics Division, Radiochemistry Division, Reactor Chemistry Division and Reactor Chemistry and Engineering Division were further established.
1978 Oct. The application for constructing HFR was approved.
1982 Feb. The Environmental Radionuclide Laboratory was completed.
1986 Jan. The Spent Nuclear Fuel Laboratory was completed.
1995 Apr. The research divisions were entirely reorganized (16 research divisions were reformed into six research divisions: Nuclear Safety Research, Neutron Research, Nuclear Energy Science, Fuel Cycle and Environment, Applied Nuclear Science, and Radiation Life Science. 2 laboratories; Reactor Utilization Center and Radiation Oncology Laboratory were completed)
2003 Apr. The research divisions were entirely reorganized
(Six research divisions were reformed into three research divisions: Nuclear Engineering Science, Quantum Beam Material Science and Radiation Life Science.)
2004 Mar. The Innovation Research Laboratory was completed
2005 Apr. the Rediation Oncology Laboratory was reorganized Particle Radiation Oncology Research Center.
2006 Apr. The Reactor Utilization Center was reoganized into Research Center for Safe Nuclear System.
2008 Apr. Research Division of Advanced Neutron Therapy was established.
2010 Apr. KUR low-enriched uranium core reached the first criticality.
2010 May. KUR low-enriched uranium core achieved the rated power of 5000 kW.
2018 Apr. Kyoto University Research Reactor Institute (KURRI) was renamed Institute for Integrated Radiation and Nuclear Science, Kyoto University (KURNS)