Lung cancer is one of the most common malignancy worldwide and accounts for more deaths per year than breast, prostate, colon and ovarian cancers combined. CT scan is very effective in early detection of lung cancer. Since most of the cases are detected at a late stage, when therapy is more often for palliative purposes or for increasing the survival. Therefore, early detection will definitely improve the mortality rate, 5 year survival of patients and will also reduce the financial burden on health care system. It also reduces the need of biopsy which decreases patient's compliance and increases the morbidity of the disease. CT scan is a safe, non-invasive and easily accessible modality which can help the clinician in diagnosing as well as staging Bronchogenic Carcinoma.