Mirabilis jalapa Linn. (Nyctaginaceae), commonly referred to as the Four O'clock plant (Sinhala name: Hendirikka), is a popular ornamental plant grown for the beauty of its flowers and used in folklore remedies. This plant is used to treat a variety of disease conditions around the world. It is widely used for abdominal colic, aphrodisiac, boils, diarrhea, inflammations, genitourinary disorders, muscular pain, and other issues by people from various countries. This plant contains several phytochemical compounds isolated from its parts, such as alkaloids, brassicasterol, carbohydrates, flavonoids, glycosides, phytosterols (beta-sitosterol and stigmasterol), oleanolic acid, trigonelline, and ursolic acid. This plant has been studied for its anti-inflammatory, antimicrobial (antiviral, antibacterial, and antifungal), antioxidant & cytotoxic, anti-tumor, anti-nociceptive, antihistamine and immune modulatory, anti-tubercular induced hepatotoxic effect, antiparasitic, dermatological, and hypoglycemic and antihyperlipidemic properties. It is also used as a reductant in the production of gold nanoparticles. This research aims to review the literature on Mirabilis Jalapa’s morphology, ethnomedicinal, phytochemical, and pharmacological properties.