Thymus is widely distributed in the world. Because its leaves are rich in terpenoids and other bioactive compounds, it has a strong aromatic smell and significant pharmacological activity. It is not only used as spice, cooking material and feed additive, but also as a traditional medicinal plant, which exert antiviral, anti-inflammatory, antioxidation, immunological, and antimicrobial effects. Thymus is also an ideal aromatic horticultural plant. Its plant type is highly related to its ornamental value. The content of terpenes and the development of secretory glandular hairs are closely related to aroma. However, the molecular mechanism of these traits is still unclear.