Abstract: Oleuropein is a natural cleaved cyclic enol ether glucoside polyphenolic compound, which has bioactivities such as antioxidant, anti-inflammatory, and anti-apoptotic. It can improve human chronic diseases such as hyperglycemia, hypertension, hyperlipidemia, obesity, and cancer by regulating body metabolism, modulating gene expression and changing enzyme activity. At the same time, it has a protective and restorative effect on various organs. This article summarizes and compares the latest research on the bioactivities of oleuropein, with the aim of providing a scientific evidence for the development and application of oleuropein in food, medicine, and health products.