Moringa oleifera is among the most commonly cultivated plant all over the world. It has high economic impact due to the medicinal and nutritional values. The seeds of M. oleifera also contain various constituents that are useful for therapeutic purposes. The aim of this study was to quantify some important antioxidant compounds of M. oleifera seed extract. Total phenolics (TP), total tannins (TT) and total flavonoids (TF) content were determined by colorimetric method. The results showed that the seed extract contain total phenolics of 10.179 ± 2.894 (mg Gallic acid equivalents / g dry matter) which is higher compared to flavonoid 2.900 ± 0.0002 (mg Quercetin equivalents / g dry matter) and tannic acid of 0.890 ± 0.020 (mg Gallic acid equivalents / g dry matter). Total phenolic content of the seeds is likely to be a key for determining the free radical scavenging and ROS reducing ability of the seeds.