Rheum undulatum L. has been commonly used as a cure for hematemesis, dropsy, and haematuria in the Oriental medicine for a long time. The main constituents of R. undulatum are chrysophanol and emodin, which are an antioxidative substance that has an anthraquinone structure. In the present study, to develop a new anti-aging agent, we examined the antioxidant activity and the inhibitory effect of the R. undulatum extract on the synthesis of MMP-1 in UVA-irradiated human dermal fibroblasts and MMP-1 activity. The R. undulatum extract was found to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals and superoxide radicals in the xanthine/ xanthine oxidase system by a dose-dependent manner, respectively. UVA-induced MMP-1 expression was reduced about 79.5% by 1 ${mu}g$/ml of the R. undulatum extract and also inhibited MMP-1 activity in a dose-dependent manner. In conclusion, it was observed that the R. undulatum extract has the antioxidant activity, regulation of UVA-induced MMP-1 production, and inhibition of MMP-1 activity. Therefore, these results suggest that the R. undulatum extract can be developed as a new anti-aging component of cosmetics.