Solid pseudopapillary tumor of the pancreas (SPTP) is a rare primary pancreatic neoplasm of unknown etiology, occurring most commonly in young women. It is a neoplasm with a low malignancy and a good prognosis after surgical removal. For this reason it is important to distinguish this tumor from other pancreatic tumors and, in particular, from the more frequent carcinomas. Two cases of SPTP are presented with a review of the literature. The first case was of a 67-year-old woman with a 2 cm mass in the head of the pancreas and the second was of a 44-year-old woman with a 6 cm mass in the head of the pancreas. In both cases the pancreatic lesions were shown by ultrasonography and a computed tomography scan. The biopsy performed under ultrasound guidance did not allow a certain pre-operative diagnosis and, for this reason, the two patients underwent a pancreaticoduodenectomy as in cancer of the pancreas. Only histological examination permitted a definite diagnosis of SPTP. In the second case a histopathological pattern indicated a low malignant potential, while in the first case the neoplasm showed an infiltrative growth into the surrounding pancreatic parenchyma, suggestive of high malignant potential. Some authors consider this latter neoplasm as a subgroup of SPTP which distinguishes itself through its higher malignant potential. Our experience suggests that aggressive surgery must be chosen in all cases where a pre-operative certain diagnosis is unavailable.