Magnetic nano radioactive medicine and its preparing method

The present invention provides a magnetic nano radioactive drug and its preparation method. Said method includes the following steps: 1. making magnetic nano microparticle undergo the process of surface chemical modification; 2. fixing and carrying ligand; and 3. making radioactive nuclide marking treatment of the ligand. Said invented magnetic nano radioactive drug has good stability underto the physiological condition. Said invention can make the nano characteristics of magnetic nano microparticle, magnetic property and therapeutic property of radioactive nuclide be combined together, and can use external magnetic field to make radioactive drug be quickly concentrated and collected on focal region so as to raise therapeutic effect and can reduce toxic side effect of killing normal tissue cell.