Background: Lung cancer is the most frequent cause of death in both men and women. Smoking is the greatest risk factor for lung cancer and the relation of human papillomavirus (HPV) infection with lung cancer has been reported. HPV can be detected in small cell lung cancer samples with the methods like in situ hybridization, polymerase chain reaction (PCR), Southern blotting, dot blotting. Objective: We aimed to detect and type HPV infection in non-small cell lung carcinoma tissue samples. Methods: Tumor samples from 40 patients were collected during surgery and PCR and restriction fragment length polymorphism (RFLP) were used in order to detect HPV infection in the samples. Results: Two HPV DNA were detected among 40 of the patients, revealing a low frequency of HPV in the samples. Conclusions: HPV can be regarded as an environmental factor in tumor development. There might be a relationship between HPV infection and some non-small cell lung cancers, especially in the smoking group. Copyright (C) 2004 S. Karger AG, Basel.