Antioxidant activity and inhibitory effect on oxidative DNA damage of ethyl acetate fractions extracted from Cone of Red Pine (Pinus densiflora) were investigated to find utilization of Cone, by-product of Red Pine, thrown out after berry shatter, as a new natural plant resource. Cone from P. densiflora was extracted with methanol (MeOH) and separated to petroleum ether, ethyl acetate and water fraction. Among them, ethyl acetate fraction was used. The antioxidant activity was conducted by the 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical, 2, 2'-Azino-bis (3-ethylbenzothiazoline-6 sulfonic acid) diammonium salt (ABTS) radical scavenging assay, Fe 2+ chelating assay and reducing power assay. The inhibitory effect on oxidative DNA damage was determined by DNA cleavage assay using φX-174 RF I plasmid. The results of DPPH and ABTS radical scavenging activity at 200 ㎍/㎖ of extracts were 86.50% and 95.80% respectively, which were similar figures compared with L-ascorbic acid as control. Fe 2+ chelating activity was 77.96% and reducing power was 0.77 at 200 ㎍/㎖. Total phenolic component was 27.29±0.3 ㎎/g and Vitamin C content was 1.84±0.1 ㎎/g. Also ethyl acetate fraction from Cone has inhibitory effect, using φX-174 RF I plasmid on DNA cleavage assay. In conclusion, Cone, by-product of P. densiflora, showed high antioxidant activity and inhibitory effect on oxidative DNA damage. Therefore this study suggests Cone, useless by-product, can be developed as a new natural plant resource with lots of utilization such as an effective antioxidant, natural medicine, food, cosmetics and so on.