This chapter provides a comprehensive analysis of the principal techniques employed in the characterization of nanomaterials, which is essential for understanding their properties and potential applications. It begins with optical techniques such as UV-Vis spectroscopy and photoluminescence, which reveal critical information about electronic structure and physical properties. X-ray diffraction techniques for crystallographic analysis are then examined, followed by electron microscopy methods that enable direct visualization of nanomaterials. The discussion extends to size and surface analysis techniques, including dynamic light scattering and BET surface area analysis, which provide crucial data on particle dimensions and surface properties. The chapter concludes with a methodological comparison that guides researchers in selecting appropriate techniques based on specific research requirements, emphasizing the complementary nature of these characterization methods and their synergistic use in nanotechnology research and development.