In this chapter, X-ray imaging technology is comprehensively discussed, and the composition and working principle of X-ray imaging system are introduced in detail. The chapter focuses on the types of X-ray detectors and their role in image quality, including traditional film radiography, computerized radiography (CR), and digital radiography (DR). Further, the radiography technology based on flat panel detector is discussed, especially the application of photon counting detector (PCD) in scanning. In addition, new X-ray imaging techniques such as computed tomography (CT), diffraction tomography, and photon counting computed tomography (PCCT), as well as dual-energy and multi-energy CT techniques, are introduced. At the same time, X-ray fluorescence imaging (XFI) and ghost imaging techniques are discussed. Finally, the potential of metal halide perovskite materials in X-ray imaging is evaluated, and the development and application prospects of X-ray imaging technology are summarized. Through these contents, this chapter provides readers with an in-depth understanding and knowledge of the field of X-ray imaging.