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Strontium ferrite (SrFe₂O₄) nanoparticles with a spinel structure were prepared using the sol-gel method. The structural, dielectric, and optical properties of the nanoparticles were investigated using X-ray diffraction (XRD), LCR measurements, UV-visible spectroscopy, and photoluminescence (PL) spectroscopy. XRD results confirmed the formation of a single-phase cubic spinel structure at 700 °C. Scanning electron microscopy showed that the particles are fairly uniform, though their magnetic nature causes some aggregation. The dielectric behavior was studied at room temperature over frequencies from 20 Hz to 10 MHz. It was observed that the dielectric constant and loss increase as frequency decreases, while AC conductivity rises, which can be explained by the Maxwell-Wagner model. UV-visible measurements indicated that the energy gap of the nanoparticles decreases with increasing temperature. PL analysis revealed an emission peak in the ultraviolet region, resulting from the recombination of free excitons, also known as near-band-edge (NBE) emission.