Colorectal cancer with bone metastasis as initial manifestation is a very rare event. We have reported a case of rectal cancer presenting with sternal metastasis. A 30 year-old man was evaluated due to pain in the sternal area with a bulging mass. History and physical examination did not suggest any specific disease. A radionuclide bone scan revealed increased uptake in the sternal area, right 6th rib, and sacrum. Microscopic examination of a biopsy specimen from the sternum showed metastatic adenocarcinoma. A barium enema and CT scan of the pelvis suggested carcinoma of the upper rectum. Adenocarcinoma of the rectosigmoid junction area was demonstrated by colonoscopic examination with biopsy. He received palliative transverse colostomy for obstruction without further treatment.