The herein study aimed to isolate natural antioxidant biologically active peptides from permeate and tested their positive effect against oxidative rancidity in edible oils in comparison with synthetic antioxidant namely butylated hydroxylanisol( BHA) .The purification of the reconstituted lyophilized permeate from minerals was performed by loading on  sephadex G.10 column and isolation of peptides was carried out using electrophoresis method.The obtained  results revealed that permeate fractioned on 12.5% acrylamide gel into two  effective peptides of about 2000and 6600 Daltons for B1and B2 respectively. Variation in m.w between the obtained two peptides may be due to the variation of amino acids concentration namely aspartic, therionine, arginine, valine, methionine, phenylalanine, histidine, tryptophane, lysine which they are composed. The total antioxidant activity (TAA) of 100 µg peptide of both B1 and B2 is equivalent to 9.46 and 7.94 µg ascorbic acid, respectively. Stability results of obtained peptides showed that frying time had no effect on both peptides. Data showed that the role of derived peptides in reducing the oxidative rancidity of corn oil and butter oil in comparison with BHA and control .Incorporation of B1and B2 with sun flower oil reduced the effect of polymers content being 25% and 19%, respectively, after 6 days .Rancimat test reveled that both peptides are effective on the stability of oils similar to that obtained by BHA. The herein study proved that the isolated peptides are effective against rancidity in oils, further are recommended to utilize it in nutraceuticals and foods.