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Nd-Fe-B composite magnets with different amounts of CaF2 have been prepared by sintering at different temperatures. The microstructure and densities of the Nd-Fe-B composite magnets were investigated by scanning electron microscope and Archimedes method. The electrical and magnetic properties were measured with a four probe electrical resistivity meter and a NIM-2000HF hysteresisgraph meter. The results show that CaF2 was distributed in the grain boundary. The electrical resistances of the composite magnets increased with the increase of the amounts of CaF2, while the magnetic properties of the magnets deteriorated markedly. The electrical resistances of the Nd-Fe-B composite magnets with 3, 6 and 9 wt.% as-bought CaF2 sintered at 1050°C were 270, 320 and 400 μΩ cm, which increased approximately 17%, 39% and 74% over that of the magnet without CaF2 ( 230 μΩ cm). The maximum energy products, (BH)max, of the composite magnets with 3, 6 and 9 wt.% as-bought CaF2 sintered at 1050°C were 41.03, 35.77 and 28.66 MGOe, respectively. The densities of the composite magnets decreased with the increase of the amounts of CaF2. High energy ball milling can refine CaF2 to nanoscale and thus improve its distribution in the composite magnets. The (BH)max of the Nd-Fe-B magnets with 3 wt% CaF2 first increased and then decreased with the increase of milling time. But the electrical resistivities of the sintered Nd-Fe-B magnets with the CaF2 without milling and after high energy ball milling have little change.