Diabetes mellitus (DM), is a metabolic disease occurring via insulin secretion deficiency from the pancreas and/or an insufficiency of tissue response to insulin. The present study is intended to show of immunolocalizations of beta-galactose-binding proteins Galectin-1 and Galectin-3 in diabetic rat ovarium and their relationship with diabetes. In this study, 8 to 10-week-old, 250-300 g weighing 50 mature female rats were used, in order to establish diabetes mellitus in those animals, 60 mg/kg intravenous streptozotocin was injected to each animal. After death, diabetics and non-diabetics rats's routine tissue processing steps is done to rat ovarial tissues for immunohistochemical investigation. Strong expressions of Galectin-1 and Galectin-3 were observed in the ovarial germinal epithelium and vascular endothelial. While the strong intense expression of Galectin-1 was seen in the zona pellucida, Galectin-3 expression was strongest in the cytoplesmic regions of cells. Zona pellucida has 3 protein complexes (ZP1, ZP2 and ZP3) in rats and in humans and they have the capability of recognizing the carbonhydrate fields in tissues. The strong expression of galectins in those regions could be the result of carbonhydrate binding properties expression of Gal-3 in the cytoplasmic regions of growing follicles could suggest the idea that Gal-3 could have effects on follicle growth. In conclusion, beta galactose-binding proteins Gal-1 and Gal-3 had stronger immunolocalization in diabetic rat ovarium when compared to the controls. Diabetes could increase the Gal-1 and Gal-3 expressions in the ovarial tissue.