Date palm (phoenix d'actylifera L) belonging to the family of palmaceae is an important plant in arid and semi-arid regions. It is cultivated for its fruit (dates) which generates a significant amount of seeds, and this work dealt with the valorization of this matter. The study investigated the extraction of the ground Algerian date seeds’ oil through a dynamic pilot-plant system using the supercritical carbon dioxide as the solvent. The effects of pressure (150-250 bar), temperature (313-333 K) and particles’ diameter (0.3-0.9 mm) on the extraction yield and fatty acids’ composition were studied. A three-level Box-bhenken design with three factors was adopted to assess the significance and interactions of the experimental parameters. The results showed that the particles’ diameter had the most significant effect on the extraction yield; while the pressure, the interactions between the pressure and temperature and between the pressure and particles’ diameter showed minor effects. Moreover, the predicted results from the empirical model fitted the experimental values well. The optimum yield was around 14.85%, which was obtained at the pressure of 250 bar, the temperature of 333 K, and the particles’ diameter of 0.3 mm. The fatty acids’ composition of the extracts was determined using GC-FID analysis. The results showed the compositions with 49.1 to 50.6 % of the saturated fatty acids, 41.9 to 43.6 % of the mono unsaturated fatty acids, and 7.3 to 7.8% of the polyunsaturated fatty acids, with Oleic acid of (C18:1n9) as the major constituent in the obtained oil. The extraction rates showed that the internal diffusion was the limiting mechanism, which controlled the extraction process.