<p>Magnesium alloys are widely used in aerospace and automotive industries due to their low density and high strength. However, their wear and corrosion resistance is recognized as limitations. This study aimed to overcome these limitations by incorporating Si₃N₄ nanoparticles into a silicate-based electrolyte for plasma electrolytic oxidation (PEO) treatment on MB8 magnesium alloy. The PEO coatings were thoroughly characterized using X-ray diffractometry, scanning electron microscopy, coating thickness measurement, surface roughness analysis, electrochemical workstation, and friction–wear testing apparatus. These analyses investigated the morphology, porosity, phase composition, thickness, roughness, electrochemical attributes, and friction–wear performance of the coatings. The results reveal the successful incorporation of Si₃N₄ nanoparticles into the PEO coating, which primarily consists of Mg, MgO, and Mg₂SiO₄ phases. The introduction of Si₃N₄ nanoparticles increased the coating’s thickness, porosity, and roughness. The wear resistance of the PEO-Si₃N₄ coating improved with increasing concentration of Si₃N₄ nanoparticles, while its corrosion resistance diminished. PEO coatings prepared with a Si₃N₄ nanoparticles concentration of 4&#xa0;g/L exhibited the highest roughness (1.53&#xa0;μm) and porosity (22%), but the lowest friction and the poorest corrosion resistance performance (3.58 × 10⁻⁵&#xa0;A&#xa0;cm⁻²). However, the best corrosion resistance (1.27 × 10⁻⁶&#xa0;A&#xa0;cm⁻²) of the coating was achieved with a Si₃N₄ nanoparticle concentration of 0&#xa0;g/L. Although the addition of silicon nitride nanoparticles reduces the corrosion resistance, the friction and wear properties of the sample surfaces are improved to meet the needs of engineering applications in various fields.</p>