The oviduct of Chinese brown frog (Rana dybowskii) expands specifically during pre-hibernation instead of in the breeding period. In this study, we investigated the expression of leptin receptor (Ob-Rb) in Rana dybowskii oviduct during the breeding period and pre-hibernation. Histologically, the oviduct of Rana dybowskii consists of glandular cells, tubule lumen and epithelial cells. The oviductal weight and pipe diameter also revealed significant differences, which were higher in pre-hibernation than that of the breeding period. Ob-Rb was observed in stromal cells of oviductal tissue in both the breeding period and pre-hibernation. The mean protein and mRNA levels of the Ob-Rb were significantly higher in pre-hibernation as compared to the breeding period. In addition, oviductal content of leptin was also higher in pre-hibernation than that of the breeding period. These results suggested that oviduct of Rana dybowskii might be a target organ of leptin, and leptin may play an autocrine/paracrine role mediated by Ob-Rb in regulating the oviductal hypertrophy during pre-hibernation.