Date seed extracts (DSE) obtained from ethanol and acetone extraction at different concentrations (0, 20, 40, 60, 80 and 100%, v/v) were characterized. Yield, phenolic and flavonoid contents increased as the concentration of ethanol and acetone increased up to 60 and 80% (v/v), respectively (P<0.05). The highest DPPH and ABTS radicals scavenging activities and ferric reducing antioxidant power (FRAP) were observed when ethanol and acetone were used at the concentrations of 60 and 80% (v/v) were used, respectively (P<0.05). However, the highest chelating activity was obtained when ethanol and acetone were used at a concentration of 20 and 40% (v/v), respectively (P<0.05). DSE prepared using 60% (v/v) ethanol (DSE-E60) and 80% (v/v) acetone (DSE-A80) were seen to have the tannic acid contents of 16.60 and 18.15 mg/g dry solid, respectively. Both extracts at levels of 100 and 200 ppm could inhibit lipid oxidation in both β-carotene linoleate and fish mince model systems. Therefore, it can be concluded that DSE-E60 and DSE-A80 can potentially be used as an alternative source of natural antioxidant.