This study examines the application of nano lubricants on AISI 52100 steel surfaces. Spherical SiO2 nanoparticles, ranging in size from 30 to 50 nm, are utilised to formulate the nano lubricants. Oleic acid (OA) serves as a surface-capping agent for SiO2 nanoparticles. The morphology and crystallinity of these nanoparticles are analysed using high-resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD). Fourier-transform infrared spectroscopy (FTIR) is employed to verify the presence of OA on nanoparticle surfaces. The tribological properties of nano lubricants are assessed using a Block on Ring Tribological Test Rig. The findings indicate that SiO2 nanoparticles at a concentration of 0.5 wt.% achieve the greatest reduction in the coefficient of friction (COF) and scar width, with decreases of 48.27 % and 27.11 %, respectively.