We report on a patient with a microcystic adenoma of the head of the pancreas. Cystic neoplasms of the pancreas comprise only about 2% of all exocrine tumours. They can be divided into two distinct groups with different prognoses: the microcystic glycogen containing tumours, which are always benign and the mucinous cystic tumours, the majority of which shows malignant dysplasia. Clinically they manifest as a palpable abdominal mass with unspecific upper abdominal pain. Preoperative diagnosis is difficult to achieve. Computer-tomography and ultrasound are the main radiological facilities that allow some degree of differentiation. During operation a frozen section is mandatory to differentiate between a pseudocyst and a real cyst with epithelial wall. Resection of the tumour is the therapy of choice. The prognosis of the microcystic adenoma is good, the prognosis of the mucinous cystadenoma-cystadenocarcinoma is much better than the prognosis of the adenocarcinoma of the pancreas.