Abstract: Ni nanoparticles filled carbon nanotubes were successfully prepared by the anodic arc discharging plasma utilizing self-designed and fabricated experimental apparatus. The composition, morphology, microstructure and magnetic properties of the products by this process were investigated via the high-resolution transmission electron microscopy (HRTEM), XRD, TEM, X-ray energy dispersive spectrometry (XEDS) and vibration sample magnetmeter (VSM). The experiment results show that most of the products are filled with the metallic nanoparticles, while the particles inside are face centered cubic(FCC) structure Ni, and the outside are well-graphitized nanotubes. The diameter of carbon nanotubes ranges from 30 nm to 40 nm, with the wall thickness approximately 5-8 nm. The particles encapsulated in carbon nanotubes are scattered and noncontinuous homogeneously in spherical or ellipsoidal shapes. Magnetic property tests show that the products is super paramagnetic, with the coercivities of 78 Oe and the saturation magnetization of 33 emu/g.