Pistacia lentiscus L. (PL) is a shrub belonging to the Anacardiaceae family, used in traditional medicine to treat various disorders in the Commune of Ajdir from Al Hociema province. The conducted study focused on determination of the polyphenols and flavonoids contents by spectrophotometric and in vitro evaluation of the antioxidant and anti-inflammatory capacity. Determining total polyphenols shows the aqueous extract with a higher concentration of 125.04±0.01mg EAG/g ES, followed by the ethanolic extract of 108.16±0.02 mg EAG/g ES. Determination of flavonoids revealed that the hexanoic extract contains a maximum of flavonoids with a level of 90.60±0.01mg EQ/g ES. The antioxidant activity of different extracts was determined through two methods: DPPH and FRAP. Aqueous and ethanolic extracts showed a high antioxidant capacity. Further, regarding anti-inflammatory activity, the ethanolic extract has good activity inhibition (92.65±0.67) followed by aqueous extract (94±0.29) at 1000 μg/mL concentration. This study found that the ethanolic extracts from P L leaves are a powerful natural antioxidant and effective anti-inflammatory agent. The results indicate the extract's effectiveness and highlight the importance of medicinal plants from the Commune of Ajdir.