Gastrointestinal surgery is a department that diagnoses and performs surgical treatment for digestive diseases such as malignant and benign tumors in the stomach, duodenum, and small intestine gastrointestinal stromal tumor (GIST), peptic ulcer, and intestinal adhesions. Among these digestive diseases, stomach cancer refers to a malignant tumor of the stomach, the first organ responsible for digestion after meals, and it is the most common cancer in Korea, ranking first among cancer deaths (25.6%). For gastric cancer, we implement gastrointestinal endoscopy, endoscopic ultrasonography, bone scan, abdominal computed tomography (CT), and positron emission tomography (PET) as necessary to establish a surgical plan through precise staging before surgery.Through this, we perform open surgery and laparoscopic surgery, and experts in various fields are performing multi-disciplinary combination therapy with multiple treatment methods.