Using the methods of nanosecond laser ablation in isopropyl alcohol and dry grinding of germanium, germanium nanoparticles were obtained for their possible application in liquid high-index immersion. Structural, chemical, and optical characterization of colloidal nanoparticles was carried out using scanning electron microscopy, IR spectroscopy, and energy-dispersive X-ray spectroscopy. Keywords: Germanium nanoparticles, laser ablation, liquid immersion, diamonds, IR spectroscopy.