The core aim of this paper is to report the isolation and characterization of Nigella sativa L. and Allium cepa L. seed oil. The oil extraction was done by the Hydraulic press. The hydraulic press is equipped with a hydro-electric power connected to a jack screw which compresses the sample inside a metallic cylinder surrounded by a resistance controlled by a thermostat. The oil yield was the ratio between the mass of oil extracted and the mass of the sample. The viscosity of Nigella sativa L. and Allium cepa L. was 28.32±0.56 and 21.36±1.06 respectively. The Specific gravity of Nigella sativa L. and Allium cepa L. was 0.83±0.19 and 0.61±0.92. The Acid value of Nigella sativa L. and Allium cepa L. was 3.05±1.63 and 2.73±2.11. The % free fatty acid, saponification values, unsaponification values and peroxide value of oil was also computed. The present work carried out to suggest exploring of title plants for chemical constituents and pharmacological action.