The Synchrotron Light Research Institute (SLRI) is a Public Organization under the supervision of the Ministry of Higher Education, Science, Research and Innovation of the Royal Thai Government. The institute operates the Siam Photon Laboratory (SPL) which is the first synchrotron facility of Thailand. The SPL services synchrotron light from the Siam Photon Source (SPS), a 1.2 GeV synchrotron light source. Many experimental techniques are available at the SPL for Thai and international users. 

The Siam Photon Project was approved by the government of Thailand in 1996 to develop the Siam Photon Source (SPS), the first synchrotron light source in Thailand. Major parts of the source were transferred from the shut down SORTEC laboratory, Japan. The storage ring was redesigned for 1.2 GeV operation. The Siam Photon Project was managed by then the National Synchrotron Research Center (NSRC) which was established under the resolution of the Cabinet of the Thai Government met on 5 March 1996. At that time, the Cabinet agreed on the establishment of the NSRC Project under supervision of the Ministry of Science, Technology and Environment. The project aimed at promoting basic and applied scientific research in Thailand. The NSRC was located at the Technopolis of Suranaree University of Technology in Nakhon-Ratchasima. Later, the Synchrotron Light Research Institute (SLRI) was established to replace the NSRC.