Ni1-xZnxFe204 (0.0≤ x≤1.0) nanoparticles have been prepared by the polyvinyl alcohol (PVA) sol-gel method.The lattice parameter of Ni-Zn ferrite nanoparticles is larger than that of the bulk material. The variation of saturation magnetization (Ms) as a function of x has been studied. The M ssbauer spectra of the samples at room temperature showed the presence of ultrafine particles, exhibiting superparamagnetic relaxation. At higher annealing temperature,the portion of the ferromagnetic ultrafine particles increased.