Alzheimer's disease is a complex neurodegenerative disorder whose exact etiology is still not fully understood. In recent years, the application of metabolomics has provided new perspectives to unravel the complex biological mechanisms of Alzheimer's disease. By quantitatively analyzing a comprehensive range of metabolites in biological samples, researchers are able to identify metabolic changes associated with Alzheimer's disease, providing data to support the exploration of potential diagnostic markers and therapeutic targets. This paper reviews research advances in metabolomics in revealing metabolic changes, identifying biomarkers, and detection tools for Alzheimer's disease. Metabolomics studies have confirmed the presence of reduced brain energy metabolism, abnormal membrane phospholipid metabolism, and imbalances in pathways related to lipid, amino acid, and choline metabolism in patients with AD. These findings emphasize the importance of metabolomics in AD and provide valuable information for future research directions and clinical diagnosis.