Bioassay-guided fractionation of the methanolic extract from the roots of Cynanchumatratum has resulted in the isolation of three newpregnaneglycosides (1–3) along with four known compounds (4–7). Their structures were identified by analysis of the spectroscopic data including extensive 2D NMR. All of the isolates were evaluated for their potential to inhibit the melanin production in α-melanocyte