To use mountain ginseng adventitious roots (MGAR), which is superior in functionality compared to ginseng, and to mass produce raw materials as a functional cosmetic material, the antioxidant and cosmeceutical activities of the extracts of MGAR at different ethanol concentrations (0, 20, 40, 60 and 80%) were compared and analyzed. At first, different ethanol concentrations were compared to determine the best solvent for the extraction of phenolic compounds from MGAR. An 80% ethanol extract with 10.07 mg of gallic acid equivalents/g sample and 0.94 mg of quercetin equivalents/g sample was the best solvent in the extraction of phenolic compounds. However, the 60% ethanol extract had the highest antioxidant activity, evident by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, Trolox equivalent antioxidant capacity (35.01 mM Trolox/g sample) and ferric reducing antioxidant power (460.94 mM FeSO4/g sample). However, the inhibitory activities of the 80% ethanol extract from the MGAR against tyrosinase and elastase were higher than those of the other extracts. The results of this study show that the extract of MGAR can be used as an easily accessible source of natural antioxidant and as a possible cosmetic ingredient in the cosmeceutical industry. However, the components responsible for the antioxidant and cosmeceutical activities of the MGAR extracts are currently unclear. Therefore, it is suggested that further studies should be carried out to isolate and identify the antioxidant and cosmeceutical components in MGAR.