Medicinal plants are used for the prevention and treatment of many diseases as they are rich in phytochemical constituents (like terpenes, flavonoids, and alkaloids) responsible for the pharmacological effects of these plants. Genus Melaleuca named the tea tree, belonging to the family Myrtaceae, is cultivated in Australia as well as in the Pacific and some regions of Asia. It has been employed in Australian traditional medicine for its broad antimicrobial activity because of its contents of phenolic compounds, monoterpenes, tannins, flavonoids, sesquiterpenes, and essential oils. Owing to the valuable uses of plants of genus Melaleuca, for different medical purposes, it was deemed interest to summarize the previous studies reported from 2004 to 2020 in the available literature about the phytochemistry and pharmacological potential of both volatile and non-volatile components of Melaleuca species. Accordingly, this article may help researchers work on plants of genus Melaleuca to promote clinical applications towards the development of novel drugs of diverse pharmacological activities, including inhibitory effects on COVID 19 obtained from Melaleuca species
