The clinical, gross anatomical, light microscopic and ultrastructural features of two cases of adenocarcinoma of the pancreas of childhood are presented and compared with adult carcinoma of the pancreas. Both tumours showed acinar differentiation and zymogen granules were demonstrated by electron microscopy. A limited immunohistochemical study suggests that staining for α1‐antitrypsin may provide a marker for acinar differentiation. The histogenesis of this tumour is discussed in relation to the possible origins of islet cel