In situ hybridization and immunohistochemistry were performed to detect insulin-like growth factor II (IGF2) in tissue sections obtained from a patient with hypoglycemia in association with primary meningeal hemangiopericytoma and metastatic foci in the liver. High levels of IGF2 mRNA and IGF2 peptide were detected in both primary and metastatic tumor cells, although the serum IGF2 level was within the normal range. Because the serum level of IGF binding protein-3 was low, whereas the serum insulin level and other endocrinological examinations were normal, we speculate that the mechanism of the hypoglycemia was associated with the tumor-produced IGF2.