Aorto-caval fistula is a rare complication of infrarenal abdominal aortic aneurysm /AAA/, and it occurs when the aneurysm ruptures into inferior vena cava. Literature indicates that such a communication is present in less than 2% of the elective AAA resections and in 3%-6.97% of the cases of AAA ruptures. From 1986 and 2000 in the University Hospital "St. Ekaterina" 207 elective AAA cases and 43 ruptured AAA cases underwent surgery. In 2 cases (4.65% of the ruptured AAA) we encountered aorto-caval communication. We report a patient with infrarenal AAA having significant oedema of lower extremities bilaterally, treated in another hospital for iron deficiency anemia and vegetative disorders. Patient presented for consultation and abdominal Echo showed AAA. The angiogram performed demonstrated aorto-caval fistula. At surgery bifurcated graft was implanted successfully. This is the first case of diagnosed prior to surgery aorto-caval fistula followed by successful surgery reported in Bulgaria.