Nickel-zinc ferrite (NZF) thin films grown on single-crystal silicon and glass substrates were produced using RF magnetron sputtering. XRD, FE-SEM, AFM, UV-vis, and VSM tests were performed to determine the phase composition and surface topography, along with the optical and magnetic properties of the NZF ferrite thin films. All samples had a spinel structure, and the average crystallite sizes, which showed growth with increasing annealing temperature, ranged from 19-31 nm. Optical investigations using UV-visible spectroscopy showed that light transmittance in the visible range increased with increasing annealing temperature. Also, FE-SEM and AFM images showed an increasing trend in grain size (from 32 to 42nm) with increasing annealing temperature and a decrease in surface roughness, both of which can affect the optical properties of the films. These structural changes were consistent with the optical behavior of the films and were effective in reducing light scattering and improving transparency. Atomic force microscopy evaluation of the annealed thin films, according to profilometry tests, showed a deposition height of 198 nm, confirming the FE-SEM data. Magnetic evaluation of the NZF/Si thin films showed an increase in MS values from 42 to 59 emu/g and a decrease in HC values from 98 to 50 Oe with increasing annealing temperature, from 700 to 900 °C. These results indicate that by optimizing the annealing temperature, NZF films not only improve their soft magnetic properties but also acquire suitable optical characteristics, facilitating their application in magneto-optical devices and high-frequency technologies.