Bioassay-guided fractionation has led to the isolation of triterpenoid saponins such as Acutoside A (3-O-[O-${eta}$-D-glucopyrano$yl-(1${ o}$2)-O-${eta}$-D-glucopyranosyl] oleanolic acid) from the whole plants of Viola hondoensis. Among them, Saponin 1 exhibited potent inhibitory activity against matrix metalloproteinase (MMP)-1, and prevented the UV-induced changes in the MMP-1 expression. In addition, compound was isolated from this plant for the first time.