To investigate the value of simultaneously obtained brain computed tomography (CT) and magnetic resonance imaging (MRI) to diagnose brain metastasis in non-small cell lung cancer (NSCLC) patients with or without neurological symptoms. Sixty-two patients (58 male, 4 female) who were admitted to Yedikule Chest Hospital and Thoracic Surgery Center between January 2000-December 2003 and whom were diagnosed with NSCLC were included in the study. Ages of patients varied between 40-85 (61 +/- 11). All patients had hemogram and routine blood chemistry as well as chest X-ray, thorax CT, brain CT, brain MRI, FOB and a complete neurological exam. Brain metastasis were detected in 22 of 62 (35.5%) patients by using brain MRI and 16 (72.7%) of these hadn't had any neurological symptoms or signs. The difference to detect the brain metastasis between brain MRI and CT was statistically significant (p < 0.01). Nine of the 22 cases (14.5%) who were found to have brain metastasis by using MRI were stage I. While brain CT showed solitary brain metastasis in five patients, 4 (80%) of them were found to have multiple metastases when MRI studies were used. We concluded that, in an attempt to make correct staging and treatment of NSCLC and hence to investigate the brain metastasis in NSCLC patients including early stage ones, brain MRI is superior to brain CT study.