Abstract.With the continuous advancement of clinical diagnostic techniques, including imaging technology, the incidence of confirmed multiple primary cancers or double primary carcinoma increases yearly. However, studies reporting synchronization surgery performed for primary dual esophageal gastric cancer are rare. The present study reports the case of a patient with double primary esophageal-gastric cancer, located in the thoracic cavity segment of the esophagus and gastric antrum of the stomach, respectively. The gastric cancer was diagnosed by endoscopy biopsy with concomitant esophageal cancer. The patient underwent gastric cancer resection, and pedunculated remnant gastric interposition esophagogastric side anastomosis was performed with gastrojejunostomy Billroth II anastomosis behind the colon. Abdominal cavity lymph node dissection was also performed. The esophagealgastric double primary cancer was simultaneously excised and the gastric regions were used in the construction of the upper gastrointestinal tract: The surgery was successful. However, two weeks after surgery, upper gastrointestinal imaging revealed esophagogastric anastomotic leakage. Subsequently, an esophageal stent was inserted and antibiotics and additional treatment was administered. Follow-up one year after surgery revealed that the patient was well and remained in a stable condition.