Renal hypoplasia refers to a congenitally small kidney where there is essentially normal residual parenchyma but smaller calyces, lobules, and papillae. This anomaly can be divided into two broad groups: complete (global) renal hypoplasia and segmental renal hypoplasia. In this study, a 3 days-old simmental calf was diagnosed with renal hypoplasia and unreconstructed exstrophic bladder. It presented very low body temperature, pulmonary distress and tachycardia in preoperative clinical examinations along with inability to urinate for 3 days according to its owner's claim. Urine bladder cannulation showed no urine in the bladder. pH, pCO2, PO2, cHCO3, cSO2, were measured as 7.352, 41,3 mmHg, 29.5 mmHg, 22.9 mEq/L, and 53.1%, respectively. The concentrations of Na+ (mmol/L), K+ (mmol/L), Ca++ (mmol/L), Cl- (mmol/L), cTCO2 (mmol/L), Hct% and cHgb (g/dL) were seen as 128, 7.1, 0.47, 103, 24.2, 19 and 6.5, respectively in blood hematological and biochemical examinations. Polycystic areas were also detected in the area of kidneys in ultrasonographic examination. Diuretics along with fluid theraphy were not effective on the urine flow from bladder, and the calf died on the 3rd day of its life.