Leptospirosis, a reemerging zoonosis, is an important cause of vasculitis, renal, and hepatic disease and should be a potential diagnosis for dogs presenting with hemorrhagic, uremic, or icteric symptoms, particularly in endemic areas. It is a serious disease in dogs with a reported case-fatality rate of 10 - 20 %. A case will be presented of a dog infected with serovar grippotyphosa that had fulminant liver failure. An overview of the etiology, epidemiology, clinical presentation, diagnosis, and treatment of canine leptospirosis will also be covered.