A 6 yers old German Shepherd dog was diagnosed to a ruptured gallbladder subsquently causing a diffuse peritonitis with bile-contaminated ascites. Surgical exploration could not determine its causes of pathogenesis. A marked leukocytosis and increased alkaline phosphotase were the pronounced clinical pathologic features. Delayed surgical exploration was critical therapeutic failure of this particular case. An immediate surgical intervention could be a life saving therapy of choise. The author report an uncommon clinical case presentation of the ruptured gallbladder in a dog and an importance of immediate surgical correction.