Gastrointestinal autonomic nerve tumor (GANT) is an uncommon form of gastrointestinal stromal tumor (GIST). We report a case of a 67-year-old woman with Parkinsonism, who had an abdominal mass incidentally detected by image studies. The neoplasm arose from the distal transverse colon and was totally excised by a left hemicolectomy. Histopathological and inmmunohistochemical studies revealed a stromal tumor toward neural differentiation with a diagnosis of GANT. The patient underwent surgery with an uneventful hospital stay. The surgical intervention, and pathological findings, along with their possible relationship to Parkinsonism are discussed. To our knowledge, this is the first case of transverse colon GANT described in the literature.