<p>Extended reality (XR), which encompasses virtual reality (VR), augmented reality (AR), and mixed reality (MR), has advanced rapidly in the field of medical radiation, transforming diagnostic radiology, nuclear medicine, radiation therapy, and radiation protection education. XR enables the immersive visualization of 3D anatomical structures generated from CT and MRI data, thereby enhancing spatial understanding, medical education, and surgical planning. Patient-specific 3D models overlaid onto the real environment through AR/MR support intuitive intraoperative navigation, improve procedural accuracy, and reduce operation time. In radiology, XR-based virtual reading rooms integrate 2D/3D digital imaging and communications in medicine (DICOM) images, facilitating interactive interpretation and collaborative training. Haptic-integrated XR further enhances training effectiveness by combining tactile and visual feedback. In nuclear medicine, AR assists in sentinel lymph-node biopsies and the real-time visualization of radiopharmaceutical distribution. Radiation therapy applications include AR-guided patient setups, VR-based training systems for equipment operation, and improved patient education through interactive XR simulations. XR also plays a vital role in radiation protection by visualizing scattered radiation using WebXR, VR, and AR platforms, enhancing safety awareness among medical personnel. Emerging systems that integrate XR with real-time tracking enable personalized dose estimation during fluoroscopy. Despite these advantages, challenges remain in terms of implementation costs, registration accuracy, hardware limitations, workflow integration, and the shortage of XR-proficient personnel. Establishing standardized frameworks and evidence-based validations are essential for broader adoption. XR has significant potential to enhance safety, efficiency, and educational quality across the field of medical radiation.</p>