Abstract： Objective To investigate the risk factors of upper gastrointestinal hemorrhage in elder patients with lung cancer after operation,providing the basis for clinical prophylaxis and treatment of complications.Methods 360 elder patients with lung cancer in department of thoracic surgery of our hospital were enrolled from Jun 2005 to Dec 2010,the complications after operation were reviewed retrospectively.Results After investigation,we found that only 10 patients(2.8％ ) had upper gastrointestinal hemorrhage.6 cases of them were fluid and electrolyte imbalance,8 cases of them were hyoxemia,3 cases of them was hypotension after operation.8 cases of them were older than 70 years old.There was significant difference between older and smaller than 70 years old.Conclusion The incidence of postoperative upper gastrointestinal bleeding in elderly patients with lung cancer was 2.8％,which was a relatively uncommon condition in clinic.Its major risk factors were age,fluid and electrolyte imbalance,hypotension and hyoxemia caused by operation.