Tea tree hydrosol (TTH) comes from leaves and epicormic branch of Melaleuca alternifolia by steam distillation. The saturated solution is called tea tree hydrosol, and pale yellow essential oil is called tea tree oil (TTO).Melaleuca alternifolia belongs to Melaleuca genus, Myrtaceae family, native to Australia, commonly known as Australian tea tree and Melaleuca tree, grow fast and can be harvested as early as six months.76 constituents were confirmed by GC-MS. Most of them are terpenoids.Three compouds have been isolated from TTH.