Our overall pooled data demonstrated that (1) the frequency of MGMT methylation in NSCLC tissue was much higher than normal tissue samples; (2) MGMT methylation was not correlated with clinicopathological characteristics like age, sex, smoking, pathological types, and differentiated status; (3) MGMT methylation played an important role in the staging and was higher in advanced staged (III and IV) NSCLC tissue than in early staged (I and II) tissue samples; and (4) MGMT methylation could not be a prognostic factor for NSCLC prognosis. This evidence concerns the gene MGMT and non-small cell lung carcinoma.