Eugenol, a phenylpropanoid compound, is found in various dietary resources and medicinal plants. From a historical perspective, eugenol is widely employed as a flavoring agent in the food and fragrance industries. Here, this review mainly focuses on recent advances in eugenol with respect to its versatile physiological roles in health and disease and discusses the mechanisms. Emerging evidence has highlighted that eugenol exhibits multiple biological activities in cancer, diabetes, obesity, cardiovascular diseases, and neurodegenerative diseases. It also has analgesic, anti-inflammatory, and antioxidant qualities and has lethal or inhibiting effects on various viruses, bacteria, fungi, and parasites. The manuscript also contains some patents that have been filed thus far regarding the production and application of eugenol. Overall, these benefits make eugenol a promising nutritional supplement which fulfils its historical function as a flavoring agent, opening up new possibilities for the creation of therapeutic agents for the treatment of disease.