 Gold nanoparticles, LNPs, have gained significant interest due to their unique optical, electronic, and physical-chemical properties. These particles have been used in a variety of medical applications, such as drug and gene delivery, photothermotherapy, PTT, photodynamic therapy, PDT, and radiation therapy, RT. Additionally, they have been used in diagnostic, X-ray imaging, CT, and other biological activities. This review provides a comprehensive overview of the synthetic methods, characterization techniques, and applications of ONPs in the medical field. This article was authored by Xiaopei Hu, Yuting Zhang, Tingting Ding, and others.