In this study, we have investigated the antioxidant activities of the leaves of Smilax china Linne in order to find the antioxidant substances which has an scavenging effect of reactive oxygen species (ROS) from natural products. As a result, EtOAc and n-BuOH extracts of the leaves of Smilax china Linne exhibited potent antioxidant effect on various antioxidant experiment. The major components of antioxidant activity were isolated from EtOAc and n-BuOH extracts of the leaves of Smilax china Linne. Their structure of compounds were identified as kaempferol-7-O-${alpha}$-L-rhamnopyranoside and kaempferol-3,7-O-${alpha}$-L-dirhamnopyranoside by spectroscopic evidence, respectively. Antioxidant activities were observed in kaempferrol-7-O-${alpha}$-L-rhamnopyranoside at 23 ${mu}g$ and in kaempferol-3,7-O-${alpha}$-L-dirhamnopyranoside at 27 ${mu}g$ as concentration of DPPH 50% reduction.