The association between pancreas adenocarcinoma and breast infitrative ductal carcinoma is extremly rare. A 55-year-old woman was diagnosed as having a pancreatic adenocarcinoma. The patient underwent a Whipple operation. At the pathology consultation; result was well- differentiated adenocarcinoma, Six months later, patient came to routine polyclinic control with breast mass. After the true-cut biopsy, invasive ductal breast carcinoma was detected in pathological examination. The prosedure was breast conservation surgery and axillary lymph node dissection. We administered adjuvan chemotherapy and radiotherapy. We think that common genetic mechanism between pancreatic adenocarcinoma and breast infiltrative ductal carcinoma might be present. Clinicians should pay attention to the possibility associated breast cancer in preoperative screeening and follow up of patients with pancreatic adenocarcinoma.