Resveratrol, a natural product and peroxisome proliferator-activated receptor (PPAR) agonist, has been reported to exert anti-cancer effects in several tumor models. A previous study by our group reported that prostaglandin J2, a PPARγ ligand, inhibited cell proliferation in a uterine sarcoma cell line. The aim of the present study was to investigate the role of the Wnt signaling pathway in resveratrol-induced apoptosis and inhibition of cell proliferation in the MES-SA human uterine sarcoma cell line. A WST-1 assay demonstrated that resveratrol inhibited cell proliferation in the MES-SA cell line, and flow cytometry revealed that the number of apoptotic cells increased in a resveratrol dose-dependent manner. The mechanisms underlying these effects of resveratrol were speculated to involve the expression of β-catenin and its target gene, c-myc, which were examined using western blot analysis. The results revealed a dose-dependent downregulation of this β-catenin and c-myc. This effect was blunted by a pharmacological inhibitor of glycogen synthase kinase 3β. Therefore, it is likely that resveratrol inhibited the cell proliferation and increased the number of apoptotic cells, at least partially, via the Wnt signaling pathway. The present results suggest that resveratrol is a potential candidate for the treatment of uterine sarcoma.