“Rapid Milk Origin Authentication Technology” uses Fourier-transform infrared spectroscopy (FTIR) to obtain full-spectrum milk fingerprints, integrating multiple compositional indicators such as milk fat, protein, lactose, total solids, and milk urea nitrogen, combined with machine learning models to distinguish domestic from imported milk. Compared with conventional chemical or isotope analyses, this technology is rapid, reagent-free, non-destructive, and suitable for high-throughput screening. Through spectral preprocessing, feature extraction, and cross-validation, the model reduces interference caused by feeding management, seasonal climate, and processing conditions. It can also be continuously retrained as the spectral database expands, thereby improving classification stability. The technology can be applied to milk source verification, brand protection, government inspection, and import monitoring, serving as a scientific tool for domestic milk traceability management and the protection of industry competitiveness.