A 3-month-old sexually intact male German Shepherd Dog was evaluated because of signs of depression, ataxia, and collapse. Clinicopathologic abnormalities included low serum BUN and albumin concentrations and high serum liver enzyme activities and plasma ammonia and serum bile acids concentrations. Abdominal ultrasonography revealed an intrahepatic portosystemic shunt (PSS). The dog was anesthetized; via a transjugular approach, guidewires and catheters were directed with fluoroscopic guidance to locate the shunt and determine its anatomic features. Minimal changes in portal vein pressure during temporary shunt balloon occlusion enabled complete shunt attenuation, which was performed by use of a self-expanding septal occlusion device that is typically used for treatment of atrial septal defects in humans. Following initial misplacement of the device, the procedure was repeated successfully 2 months later and resulted in complete shunt occlusion. One year after this second procedure, the dog was clinically normal and serum bile acids concentration was within reference limits. In certain dogs with intrahepatic PSSs, treatment with minimally invasive interventional techniques involving fluoroscopy may reduce the morbidity and mortality rates associated with more invasive surgical procedures.