This study was carried out to investigate the flavoral essential oil components in the stems of Agastache rugosa. These components were analyzed using gas chromatography-mass selective detector (GC-MSD). The stems of Agastache rugosa were contained alcohols, aldehydes, ketones, fatty acid esters, and terpenoids. The peak area (%) of estragole was highest among its oil components and the next were pulegone and menthone. The terpenoid alcohols found were 1-octen-3-ol, chavicol, spatulenol, 3-hexen-1-ol, 2-cyclohexen-1-ol, methyl eugenol, and octaethyllene glycol. The stems also contained ketones such as pulegone, menthone, cis-isopulegone, 2-cyclohexene-1-one, 3-octanone, 1-cyclohexanone, isoindole-1- one, t-ionone, inden-2-one, as well as the aldehydes of 4-methoxycinnam and benzaldehyde. The following esters were also detected 1-isopulegone-3-yl acetate, caryophyllene oxide, acetate and benzendicarboxylic acid ester. The terpenoids in the stems were identified as caryophyllene, limonene, cyclohexasiloxane-D, germacrene-D, anethole, cadinene, muurolene, and bourbonene. Overall Agastache rugosa contained several functional oil components including phenylpropanoids and terpenoids as flavoral essential oil components for natural aromatherapy.