Abstract:A 52 year‐old female was admitted to our hospital for lung cancer. We performed upper gastrointestinal endoscopy for her complaint of epigastralgia, and diagnosed Borrmann 2 type gastric cancer on the posterior wall of the angle.Chemotherapy with CDDP and VDS was commenced for lung cancer, and endoscopic Nd‐ YAG laser local hyperthermia (Laserthermia) was carried out for gastric cancer. Nd‐ YAG laser provided computer‐controlled thermo‐monitering system was irradiated in 3W, intermittently. Laserthermia could be applied safely to the clinical endoscopy.Conclusions were as follows;1) Borrmann 2 type gastric cancer complicated with lung cancer was treated with laserthermia without severe complication.2) This is the first report that the Laserthermia controlled by computer thermo‐system was put in to clinical use.3) Laserthermia with chemotherapy was more effective than laserth