Abstract: X-rays and synchrotron radiation light sources are powerful tools for exploring the microscopic world of matter. This article reviews the discovery, physical essence, and applications of X-rays, as well as Nobel Prizes related to X-rays and the evolution of X-ray light sources. It also summarizes the generation principles of synchrotron radiation, the structure and characteristics of synchrotron radiation light sources, the development of synchrotron radiation light sources, synchrotron radiation experimental methods and applications. Moreover, it sorts out the development history and representative achievements of the research on the application of synchrotron radiation light sources at Beijing University of Technology. Finally, it outlines the future research work based on the fourth-generation synchrotron radiation light sources.