Abstract: Due to the excellent physical properties and advantages in the field of tumor therapy, lutetium 177 has attracted extensive attention in the field of internal radiation therapy in nuclear medicine. The carrier free radionuclide lutetium 177 can be used for targeted treatment of neuroendocrine tumor and prostate tumor. The carrier free radionuclide lutetium 177 can be prepared by irradiating high abundance ytterbium 176 isotope in reactor. The experimental study result found that the abundance of ytterbium 176 isotope directly affects the activity of lutetium 177. In order to meet the requirement of high abundance of ytterbium 176 isotope, in view of the characteristics of high primary separation coefficient and good universality of electromagnetic method, the key process parameters of electromagnetic separation and preparation of high abundance ytterbium 176 isotopes were studied. Ultra dry YbCl₃ with purity of 99.99% was selected as the separation raw material according to the requirements of electromagnetic isotope separation on raw materials. The trajectory of ytterbium ion beam in magnetic field was simulated, and the effects of magnetic induction intensity and beam opening angle on the dispersion of ytterbium isotope separation were given. The results are the same as the theoretical analysis. The design of nonuniform field will increase the dispersion between isotopes, reduce the sputtering contamination between isotopes, and then improve the abundance of isotopes. The emission angle of ytterbium ion beam is 11°, the seven isotopes of ytterbium can be separated completely, and the dispersion of ytterbium 176 and ytterbium 174 is large. The effects of ion source parameter on the beam intensity and focusing ability of ytterbium isotopes were obtained by ytterbium isotope electromagnetic separation experiment. The main basis for judging whether the discharge parameters of the ion source are appropriate is the current intensity of the ytterbium 176 ion beam and the focusing ability Q of the ion beam. In this experiment, the ratio of the current intensity of the ytterbium 176 to the panel current intensity was taken as the embodiment of the focusing ability Q. This experiment was carried out by controlling the variable method, and the optimal combination of separation parameters was given. Finally, ytterbium 176 isotope sample with high abundance was prepared by electromagnetic separation. After separation, the ytterbium isotope in the receiver is chemically purified to obtain ytterbium 176 isotope, which is detected by mass spectrometer. The abundance of the sample reaches 98.16%. The high abundance ytterbium 176 isotope prepared in this study is chemically treated to form Yb₂O₃ compound, which is used as the target of nuclear reactor irradiation to supply the demander.