Among the main purposes in the medical industry for prevention, diagnosis, and treatment of diseases are controlling radiation doze using a state-of-the-art medical technology, and optimizing image quality. The study of radiation properties and their effect and interaction, medical imaging analysis, and nuclear medicine offer unwavering interest. Nanomaterials play a key role in the innovation, design, and development of medical technologies in health care by testing, implementation, and, development of new diagnostic and medical equipment. Because of their unique characteristics and properties, they have become the most chooseable and multipurpose devices in the medical industry. They have grasped and gained considerable attention and offer unwavering interest due to their wide extent of technological applications, especially in the medical sector. Nanomaterials have been playing a significant role in the medical sector in the production of medical devices and bone and joint replacement biosensors for replacing damaged organs, correcting abnormalities, and thus improving the quality of life of patients. In this paper, we have attempted to highlight the applications and important progress achieved by nanomaterials to give a comprehensive understanding of various medical techniques with radiation principles, medical imaging, radiotherapy, and nuclear medicine. Finally, the challenges and future trends for the development and design of safe nanomaterial for medical technology and applications have been suggested.