Abstract: The present invention provides radioactive glass microspheres for embolization and a preparation method and an application thereof. A nuclide oxide and a foaming agent are added into a glass matrix, blended and uniformly mixed for making the foaming agent decomposed and vaporized at a high temperature to generate bubbles, so as to prepare the radioactive glass microspheres for embolization with cavities. The radioactive glass microspheres for embolization have a density of 1.4-2.3 g/cm3, a nuclide loading rate of 15-40 wt % and a higher and more stable radiation dose, can achieve better distribution and deposition effects in liver blood vessels after injection, and can achieve a better therapeutic effect for hepatocellular carcinoma (HCC).