We report the case of an 86-year-old male who was admitted for intestinal subocclusion, in whom an abdominal computed tomography (CT) scan and colonoscopy revealed a colocolonic intussusception with an underlying and heterogeneous mass, failing to rule out a neoformative lesion. A left hemicolectomy procedure was carried out with regional lymphadenectomy (because of the potential neoplastic origin) through laparoscopy, and the patient had a favourable postoperative course. Pathology described 45cm of an intestinal segment, with intussusception and with a 12x7x6 cm ulcerated polypoid lesion. Lesion was revealed as high grade GIST, pathological state of pT4, N0 and free margins. The patient was treated with adjuvant Imatinib. The presentation of a colonic GIST as a colocolic intussusception causing intestinal subocclusion is an extraordinary case, and in our patient, early diagnosis with abdominal CT and free margin surgery were key for successful management.