Adult retrograde intussusception of the colon is very rare. We encountered a case of retrograde intussusception due to pedunculated adenocarcinoma of the sigmoid colon. A 54-year-old man was admitted to our hospital with left flank pain and vomiting. Retrograde intussusception was diagnosed by abdominal computed tomography and emergency surgery was performed. The sigmoid colon was firmly invaginated in a retrograde manner. Sigmoidectomy with lymph node dissection was performed after manual repositioning. The resected specimen showed two pedunculated polyps at the top of the intussusception. Microscopic examination clarified that one represented papillary adenocarcinoma in adenoma. Since more than half of retrograde intussusceptions have been reported to be caused by pedunculated malignant tumors, intestinal tract excision with lymph node dissection should be considered.