A 6-year-old neutered male golden retriever mix dog was presented for investigation of acute restlessness, increased respiratory effort, non-productive retching, and anorexia. Initial abdominal radiography revealed marked gastric dilation with a normal gastric shape and position, along with mineralized granular material in the pyloric region, consistent with a pyloric outflow obstruction secondary to suspected sand impaction. The dog was stabilized with gastric trocharization and medical management with intravenous fluids, antiemetics, polyethylene glycol via a nasogastric tube, and analgesia was initiated. The dog developed aspiration pneumonia during hospitalization and became oxygen-dependent. There was no significant improvement of clinical status despite 72 h of medical management, and surgical intervention was subsequently recommended. Exploratory laparotomy revealed a counterclockwise gastric dilatation and volvulus. The stomach was repositioned into normal anatomic position and an incisional gastropexy was performed. The dog was maintained in the intensive care unit for 4 d postoperatively. Currently, 3 mo postoperatively, the dog is healthy without recurrence of clinical signs. Key clinical message: Counterclockwise gastric dilatation and volvulus is a rare condition in veterinary medicine; however, it should be considered in a patient with acute gastric distension and signs of pyloric outflow obstruction when characteristic radiological signs of clockwise gastric dilatation and volvulus are absent, and there is radiological evidence of persistent gastric foreign material despite medical management. Misdiagnosis of counterclockwise gastric dilatation and volvulus can delay definitive surgical intervention and lead to higher morbidity and mortality.