An immunohistochemical localization of amylase was demonstrated in human pancreatic acinar cells using a commercial anti-human pancreatic amylase antibody. The immunofluorescence was mainly localized in the cell apices, and some differences in the intensity of the fluorescence was observed among the acinar cells in respect to their location from the islets of Langerhans. The peri-insular acinar cells showed a brighter fluorescence than the cells of tele-insular acini. This inhomogeneity of pancreatic amylase distribution in the human exocrine pancreas adds a further clue to the concept of insulo-acinar interaction.