Algeria, by its geographical position, is home to an exceptional biodiversity occupied by important medicinal plants. Thymelaea hirsuta, endemic species is a medicinal plant used in Algerian folk medicine for the treatment of various diseases. This work focused on the phytochemical study by liquid chromatography coupled with mass spectrometry (LC-MS) with Electrospray source (ESI) of aqueous extracts from flowers, leaves and twigs. The phytochemical results show that the different organs, more particularly the flowers constitute a privileged source of biologically active molecules belong to the family of polyphenols in which the subfamilies of hydroxycinamic acids (ferulic acid, caffeic acid, chlorogenic acid, feruloylquinic acid…), coumarins (esculetin, scopoletin, sphondine, rutarensin…) and flavonoids (Isochamaejasmine, kaempferol, apigenin…). This study confirms, scientifically, the traditional use of this plant and reveals its interest in the context of industrial pharmaceutical exploitation.