The aim of this study was to analyze the essential oil of Lavandula dentata from Algeria and to test the antioxidant and antimicrobial properties of this plant. The EO (57 constituents) included mainly α-pinene, β-pinene, nopinone, linalool, cryptone, and limonene. The plant polyphenolic contents and the antioxidant activity were determined. The antimicrobial effect of the EO and the ME was assessed against referenced and clinical bacterial strains, and also foodborne fungal isolates. The EO MIC values varied from 0.25 to 4 mg/mL and CMBs were less than 8 mg/mL except for S. aureus, clinical Klebsiella, S. epidermidis, and B. subtilis. The mold strains were significantly inhibited by the EO (87.50% to 88.33%). The MIC values were 3.60 -15.62 mg/mL and 0.5 -4 mg/mL for ME and EO, respectively. The MFC values ranged from 31 to 125 mg/mL and from 2 to 8 mg/mL for ME and EO respectively.