<p><i>Inula britannica</i>, a yellow flower belonging to the <i>Asteraceae</i> family, has traditionally been used, with its young shoots being edible and the flowers being used as tea. In addition, it has been used traditional medicine for centuries, due to the physiological activities, including anti-inflammatory, anti-tumor, and antioxidant activities. Furthermore, it exhibits various other bioactivities, including neuroprotective, anti-obesity, and antibacterial effects. The bioactivities of <i>I. britannica</i> are thought to be primarily due to the sesquiterpene components. It consists of three isoprene units, with variations reported depending on origin and isolation methods. Although sesquiterpenes are effective, they are toxic, and independent safety studies are lacking. Furthermore, research on the applications of <i>I. britannica</i> is limited, except for some studies on cosmetics and food. Therefore, this review summarizes the bioactivities, components, and safety of <i>I. britannica</i>, discusses its potential as a functional food material, and presents its overall characteristics.</p>