Abstract: OBJECTIVE To investigate the drug resistance of pathogens in elderly patients with non-small cell lung cancer and chemotherapy so as to provide references for the treatments of infection. METHODS Totally 126 cases of elderly patients with non-small lung cancer received chemotherapy in our hospital from Jan. 2013 to Jan. 2015 were collected as study objects. Samples of blood, urine, throat swab and tissue fluid were collected to identify and make drug sensitivity test. The pathogen distribution and drug resistance were analyzed. RESULTS Patients were mainly infected in respiratory tract. And upper respiratory tract infection and lower respiratory tract infections accounted for 63.49% of the total number of infections, followed by genitourinary system infection with the rate of 17.46%, oropharyngeal tract infections with 11.11%. From 126 cases which have been confirmed infected, 191 strains of pathogen were isolated, including 63 strains of gram-positive bacteria, accounting for 32.98%; 115 strains of gram-negative bacteria, accounting for 60.21%; and 13 strains of fungi, accounting for 6.81%. The drug resistance of main gram-positive bacteria to penicillin, tetracycline, clindamycin were all over 50%, especially amoxicillin and oxacillin had resistance rate >73%. But the resistance rate to sulfamethoxazole / trimethoprim was <45%. The pathogens were extremely sensitive to vancomycin and linezolid with the resistance rate of 0%. CONCLUSION Based on the analysis of distribution and drug resistance of pathogens in elderly patients with non-small cell lung cancer and received chemotherapy, we can know the constituent of main pathogens and drug resistance of those pathogens. In this way we can choose proper antibiotics according to different pathogens and drug sensitivity test results.