Laurus nobilis is an aromatic plant, common in Algeria and widely used by local people as a source of spice and for medicinal purposes. The essential oil of this plant is the subject of this work in a physicochemical and microbiological study. The extraction of the essential oil was carried by steam distillation, the yield obtained from the leaves (1.5%),pH (5,65 ), the specific gravity (0,917), miscibility in ethanol (1V/4V) ,the refractive index (1,3329) ,the optical rotation(+ 0,5°), the indices acid(2,3), ester(21,74), peroxide(2960). The organoleptic and physico-chemical characters are consistent with those obtained in the literature with some differences that can be attributed to certain factors. Evaluation of antibacterial activity showed a sensitivity of Salmonella spp. with an MIC of 2,5 mg.ml-1, and other bacteria of the intestinal flora of Westar rats: E.. coli and Lactobacillus sp. have a high potential for resistance with MICs respectively equal to 10 and 20 mg.ml-1