We investigated the effect of glutathione supplementation on feed intake, body weight gain, velvet antler yields and economics of elk yearling. Fourteen elk yearlings were divided into 2 groups. Seven yearlings in each group (control and treatment) were fed with 1.5-2.5 percent body weight (%BW) of concentrate feed for elk, voluntary intake of hay as roughage and 6 mg/kg body weight (KBW) of glutathione. The results were as follows. Average daily gain (ADG) for control elk yearlings for first 1.5 month was 0.46 kg, while that of glutathione supplemented was 0.55 kg. Although glutathione fed group had higher ADG compared to control group (p<0.05), ADG after 1.5 month showed no difference. In spring, daily DM intake per elk yearlings was 3.98 and 4.24 kg for control and glutathione supplemented groups, respectively. The statistical differences in feed intake between two groups were not observed. However, feed intake tends to increase in glutathione fed group. Production of velvet antlers for elk yearlings were 911±256 and 1066±357 g for control and glutathione supplemented groups, respectively. Statistical difference between two groups was not observed due to the high variation. In economic analysis, additional 109,110 KRW per head for the cost of glutathione resulted in 2 percent higher revenue index due to the increased antler production. In conclusion, feeding glutathione to elk deers effectively increased DM intake and ADG of elk yearlings. Glutathione supplementation in feed might increase velvet antler production as well as ADG.