The selection of suitable chelating agent for particular ferrite composition becomes critical in attaining an optimum particle size with a precise control. Since the increase in viscosity and prevention of cation segregation due to addition of chelating agent and the nature of cat-ions play crucial role in controlling the particle size. In this view nano crystalline Ni0.65Zn0.35Fe2O4 ferrites have been synthesized by sol-gel technique using PVA and PEG as chelating agents at different annealing temperatures. The heat treated samples were characterized by X-ray diffraction, FT IR spectra, transmission electron microscopy and VSM. The impact of chelating agents on the crystallite size, particle size, and saturation magnetization at different annealing temperatures has been studied as part of investigation. FT IR spectra reveal the presence of PVA and PEG in the ferrite samples up to 6000C.