This chapter deals with the analysis of mono and sesquiterpenoid composition in the leaves and stem of Artemisia amygdalina Decne obtained by hydrodistillation using a combination of capillary GC-FID and GC-MS analytical techniques. A total of 25 components in the leaf and 32 components in the stem essential oils have been reported. The leaf essential oil majorly consists of monoterpene hydrocarbons (38.2 %) and oxygenated monoterpenes (43.8 %) together constituting 82.0 % of the total oil composition. The principal components that have been identified include sabinene (10.2 %), p-cymene (14.7 %), 1,8-cineole (17.5 %), and borneol (19.8 %). The stem essential oil comprises monoterpene hydrocarbons (66.1 %), oxygenated monoterpenes (12.8 %) and sesquiterpene hydrocarbons (11.2 %). The major constituents were α-pinene (6.0 %), camphene (10.4 %), β-pinene (40.2 %), and borneol (5.7 %). A comparative analysis of the essential oil obtained from the leaves of micropropagated plants of A. amygdalina with that of the leaves of field grown parent plants has also been reported. The oil yield from the micropropagated plants has been found to be (0.05 % v/w) than the oil yield obtained from field-grown plants (0.2 % v/w). The major constituents of the field-grown plants include p-cymene (21.0 %), 1,8-cineole (24.9 %), α-terpineol (5.9 %), β-caryophyllene (4.7 %), germacrene-D (4.0 %), while as the major constituents of the micropropagated plants reported include p-cymene (11.3 %), 1,8-cineole (10.2 %), borneol (7.9 %), α-longipinene (5.5 %), α-copaene (5.5 %) and β-caryophyllene (17 %). The essential oil from field-grown plant is further dominated by the presence of oxygenated monoterpenes (41.5 %), monoterpene hydrocarbons (35.9 %) and sesquiterpene hydrocarbons (16.3 %) while as the essential oil of micropropagated plants is known to be characterized by sesquiterpene hydrocarbons (40.0 %), oxygenated monoterpenes (25.2 %) and monoterpene hydrocarbons (21.6 %).