The chemical composition of 18 oil samples of Santolina africana isolated from aerial parts at full flowering, collected in three locations in eastern Algeria was determined by GC(RI), GC/MS and ¹³C-NMR analysis. The major components were: germacrene D, myrcene, spathulenol, α-bisabolol, β-pinene, 1,8-cineole, cis-chrysanthenol, capillene, santolina alcohol, camphor, terpinen-4-ol and lyratol. The chemical composition appeared homogeneous and characterized by the occurrence of four derivatives which exhibited a conjugated alkene dialkyne moiety. They were identified for the first time in an essential oil from S. africana. The collective oil sample exhibited moderate antimicrobial and antioxidant activities whereas the anti-inflammatory activity presented a real potential. IC₅₀ value of Santolina africana essential oil (0.065 ± 0.004 mg/mL) is 5-fold higher than IC₅₀ value of NDGA used as positive control.