BACKGROUND To evaluate the clinical efficacy and the security of erlotinib in the treatment of elderly patients with advanced non-small cell lung cancer and COPD. METHODS Fifteen patients with advanced non-small cell lung cancer and COPD were treated with erlotinib 150 mg/d, and then the adverse reactions and clinical effects were recorded. RESULTS The effective rate was 20%. We analyzed the effective rate of stage III and IV, and there were no significant difference between the two (P=0.569). KPS was increased in 40% patients. Mild or moderate rash, diarrhea, nausea and vomiting were the main adverse reactions. CONCLUSIONS For elderly patients with advanced non-small cell lung cancer and COPD, the use of erlotinib might achieve better security and effectiveness.