Twenty-five young budgerigars that died with the complaints of abdominal distension and crop swelling were examined pathologically. One hundred and twelve, 8-19-day-oid chicks died at the same aviary with the same clinical symptoms over 16 months; the morbidity and mortality rate was 100%. Ascites, hydropericardium, crop and oesophagus ulcers, cardiomegaly, splenomegaly, hepatomegaly and focal hepatic necroses were the predominant necroscopic findings. The histopathological examination revealed characteristic intranuclear inclusion bodies in the liver, kidney, spleen, lung, oesophagus, crop, brain, pancreas, heart, gut, thymus and bone marrow. Avian polyomavirus infection was diagnosed after an immurohistachemical examination. This is the first report of avian polyomavirus infection in budgerigars in Turkey.