The research and application of infrared spectroscopy in the field of drug detection are focused on in this paper. ATR-FTIR used for qualitative analysis of drugs and classification of mixed drugs, and near-infrared spectroscopy used for quantitative and traceability analysis of drugs are introduced. By virtue of its characteristics of accuracy, simplicity, rapidity and practicality, infrared spectrum is effectively combined with a variety of stoichiometric algorithms, which can further provide quantitative indicators for the judgment, classification and tracing of drugs. With the further integration with artificial intelligence technologies such as machine learning and neural networks, infrared spectroscopy technology will play a huge role in the future laboratory analysis and rapid field detection of drugs.