A geriatric dog was presented for acute vomiting, anorexia and lethargy. Abdominal ultrasound was suggestive of the presence of gas within the small intestinal walls. Additional abdominal radiographs confirmed the ultrasonographic abnormalities, compatible with pneumatosis intestinalis. Explorative laparotomy revealed hemorrhagic lesions, thickened intestinal walls and serosal discoloration of the jejunum. Partial jejunectomy was performed and histopathology showed findings compatible with atypical bacterial enteritis. The dog recovered completely and did not show any clinical signs during a follow-up period of one year after surgery.