Leaf masquerade—an animal resembling leaves that are inedible for predators or innocuous for prey—is well known in insects but less so in arachnids. We report a case of a striking morphological and behavioral adaptation that can be labeled as leaf masquerade in an undescribed spider species (Poltys C.L. Koch, 1843, Araneidae) from southwest China. The female abdomen has anatomical analogues of a leaf pedicel and venation, and its color is both green and brown, thus resembling both live and dry leaves. The spider camouflages itself with pulled dead leaves among live ones. This novel natural history in a spider adds an arachnid model to the growing literature on animal masquerade.