A case of cecocolic intussusception with complete invagination and intussusception of the appendix with villous adenoma. Villous adenoma of the appendix is a rare neoplasm and intussusception of the appendix is a rare pathologic condition. A very rare case seen in a 35-year-old male with pain in the right lateral abdomen is reported. In this patient, the appendix along with the villous adenoma intussuscepted and invaginated into the cecal lumen, and presented as cecocolic intussusception. A polypoid lesion was diagnosed in the cecum by fiberoptic colonoscopy. Unlike polypoid lesions at other sites in the large intestine, polypoid lesions of the cecum may accompany intussusception and invagination of the appendix. Consequently, caution is required in performing endoscopic polypectomy in cases of polypoid lesions of the cecum. 