Polyalthia longifolia has been used in traditional system of medicine for the treatment of fever, skin diseases, diabetes, hypertension, helminthiasis etc.Now a days; there is growing interest in exploring new sources of potent natural antioxidants for the food industry. In the present study antioxidant activity of ethanolic extracts obtained from the leaves and seeds of P. longifolia along with total phenol and flavonoid content has been evaluated spectrophotometrically.The total phenol content was determined using the Folin – Ciocalteu reagent while total flavonoid content was evaluated with aluminium chloride under basic conditions. The antioxidant activity of ethanol extract of the seeds and leaves was determined by measuring the radical scavenging activity against 2, 2 – Diphenyl– 1-picryl hydrazyl radical (DPPH). .The highest radical scavenging effect was observed in leaves with IC50 = 0.5824mg/ml than in seeds with IC50 = 1.4677 mg/ml. Phenolic compounds and flavonoid contribute to this activity. The results suggest that P. longifolia is a good source of antioxidant and can be used against various free radical related disorders.