The antioxidant activity of Sargassum latifolium algae extract as well as the eco-friendly synthesis of selenium and zinc nanoparticles with biocompatible Sargassum latifolium extract were studied in the current research. Selenium and zinc nanoparticles showed a spherical shape and had an average particle size of 22.31 to 95.16nm when they are studied using transmission electron microscope. HPLC technique was used to identify the phenolic components in Sargassum latifoliumalgae extract, myricetin was the predominant polyphenol in concentration of 139.63 ppm, followed by neringein, kampherol, rosemarinic acid, salicylic acid and quercitin in concentrations of 51.89, 38.20, 30.10, 27.95, and 18.07 ppm, respectively. While, the rest of polyphenols were ranged from 12.95 ppm for p-coumaric acid to 1.45 ppm for ferulic acid. On the other hand, quinol, catechol, chlorgenic, vanillin, rutin, ellagic acid, and cinnamic acid were absent in thealgae extract. Sargassum latifolium algae extract as well as synthesis selenium and zinc nanoparticles were added as natural antioxidants to corn and soybean oils in concentrations of 200, 400, and 800 ppm and its antioxidant activity was compared with TBHQ as synthetic one. Rancimat time at 110ºC which indicated that induction period of control oils were varied from10.70 and 5.53 hours for corn oil and soybean oil, respectively. However, the treated samples with TBHQ exposed from 13.30 to 7.03 hours for both oils, respectively. Addition of Sargassum latifolium algae extract with different concentrations increase the induction periods to 28.95 and 9.87 hours for corn and soybean oils, respectively. The highest stability times were achieved when corn and soybean oils were treated with synthesis selenium nanoparticles at a concentration of 800 ppm, which were 31.78 and 12.50 hours, respectively. Synthesis zinc nanoparticles could be involved in the bio-reduction reaction in a concentration of 800 ppm to prevent oils oxidation and rancidity as reported for 26.00 and 11.13 hours for corn and soybean oils, respectively. So, Sargassum latifolium algae extract as well as selenium and zinc nanoparticles could be recommended as natural antioxidant for both corn and soybean oils due to their advantage effects on the oxidative and thermal stabilities of these oils.