Artemisia annua L. (Chinese wormwood herb, Asteraceae) synthesizes artemisinin, which is known as qinghaosu, considers as a unique sesquiterpene endoperoxide lactone. In traditional Chinese medicine, it has been used for the treatment of fevers and haemorrhoides. More researches on Artemisia annua L. and its derivatives, especially artemisinin and other metabolites will help to increase the knowledge and value of A. annua and its constituents. Phenolics from Artemisia annua consists of coumarins, flavones, flavonols, phenolic acids, and miscellaneous. Artemisinin has attracted much attention from scientists due to its potent antimalarial properties as secondary metabolites. Moreover, more attentions are focusing on the roles of artemisinin and its derivatives in treating obesity and metabolic diseases. They also have anti-bacterial, anti-inflammatory, anti-tumor, anti-protozoa, anti-helminthic, anti-fungal, anti-angiogenic and antiproliferation properties.