The pathological findings of five cases of amyloidosis associated with Cystic Fibrosis are reported. Rectal biopsy led to the diagnosis of amyloidosis in four patients. In three cases the diagnosis was confirmed at autopsy, with involvement of spleen, liver, kidneys, adrenal glands, thyroid and other organs. It seems that Secondary Amyloidosis provokes a significant, although rare, complication of Cystic Fibrosis as greater numbers of these patients survive into adulthood.