In this study, we assessed the antioxidant activities and quality characteristics of cookies containing various concentrations (0, 1, 3 and 5%) of Eleutherococcus sessiliflorus leaf powder. Antioxidant activity was estimated based on DPPH free radical scavenging activity and total content of phenolic compounds in Eleutherococcus sessiliflorus leaf powder and cookies. The quality characteristics of Eleutherococcus sessiliflorus leaf cookies were estimated based on spread factor, loss rate, leavening rate, color, texture and sensory evaluation, polyphenol contents, DPPH free radical scavenging activity, as well as spread factor of cookies significantly increased. L value, b value and hardness of cookies decreased with increasing Eleutherococcus sessiliflorus leaf powder content. Finally, the sensory evaluation showed the highest scores for cookies containing 3% Eleutherococcus sessiliflorus leaf powder. From these results, we suggest that Eleutherococcus sessiliflorus leaf is a good ingredient for increasing consumer acceptability as well as the functionality of cookies.