Abstract: As the Chinese population aged, the number of Alzheimer disease (AD) patients is gradually increased. Epidemiological studies have shown that tea consumption can help reduce the risk of AD and other neurodegenerative diseases. It may be due to the ability of functional components contained in tea to regulate the main pathogenic factors of AD. In this article, the effects of tea functional components such as tea polyphenols, theanine, caffeine, theaflavin and tea saponin on the main pathogenic factors of AD are systematically summarized. The multi-target mechanism of tea functional components from aspects of β-amyloid, Tau protein, acetylcholine, neuroinflammation and oxidative stress, etc., to effectively prevent AD is clarified. It is expected to provide a theoretical basis for daily tea drinking to prevent AD and the development of tea functional ingredients.