Supercritical fluid (SCF) technologies offer a versatile and sustainable approach to synthesizing nanoparticles with precise control over size, morphology, and functionality, suitable for various industrial applications. SCFs, particularly carbon dioxide and water above their critical temperature and pressure, exhibit liquid-like solvating power and gas-like diffusivity, making them ideal for producing particles with tunable properties. This paper explores the principles and processes of SCF technologies, emphasizing methods like Rapid Expansion of Supercritical Solutions (RESS), Supercritical Anti-solvent (SAS), and Particles from Gas-Saturated Solutions (PGSS), each demonstrating unique advantages in nanoparticle production. RESS involves rapid depressurization, allowing fine control over particle size, while SAS uses SCFs to precipitate nanoparticles from solutions, offering enhanced bioavailability and solubility for pharmaceutical applications. The PGSS technique encapsulates various compounds without requiring solubility in SC-CO2, supporting applications in food and pharmaceuticals. Advancements in SCF dynamics, such as SAS with enhanced mass transfer (SAS-EM), have enabled efficient, high-quality production of nanoparticles while minimizing organic solvent use. SCF technology has proven advantageous for industrial processes due to its ability to meet regulatory and safety requirements, particularly in the pharmaceutical and materials sciences sectors. This review underscores SCF’s role in clean nanoparticle production, exploring its application in drug delivery, catalysis, and electronic materials, and highlights ongoing research for optimizing process variables and scaling up operations. The environmental and economic benefits of SCF technologies demonstrate their potential to revolutionize industries by aligning with green chemistry principles and sustainable development goals.