The pharmaceutical properties of artemisia are partially attributed to their essential oils, containing a wide variety of active phytochemicals, such as monoterpenes, sesquiterpenes and triterpenes. Among important terpens are b-amyrin, b-caryophyllene, Linalool and b-Pinene that are used as anticancer, analgesic, antimicrobial, antioxidant and anti-inflammatory. In this study, we have examined the relative expression levels of four genes of b-amyrin synthase, b-caryophyllene synthase, Linalool Synthase, and b-Pinene Synthase in eight species of Artemisia by real-time PCR. We used 18S rRNA as a control gene. Maximum and minimum expression levels of b-amyrin synthase, b- caryophyllene synthase, Linalool Synthase and b-Pinene Synthase were observed related to A. annua at the flowering stage of A. scoparia (1.62) and the seedling stage of A. sieberi (-50.85), the flowering stage of A. campestris (56.28) and the flowering stage of A. vulgaris (-10.74), the budding stage of A. scoparia (15.86) and the budding stage of A. sieberi (-20), the budding stage of A. campestris (53.57) and the budding stage of A. diffusa (-23.49), respectively.