Lung cancer has the highest mortality rates in many advanced countries including those in Europe and America. In Taiwan, lung cancer had, in the last 10 years, the third incidence and the highest mortality rates. Currently, lung cancer is the leading cause of cancer-related deaths in Taiwan. Every year, about 13,000 people are newly diagnosed with lung cancer, and more than 9000 people die of this disease. To reduce the high mortality rate of lung cancer, many experts promote lung cancer screenings based on the results from several trials (e.g., NELSON trial, National Lung Screening Trial). However, the cost-effect impacts derived from widespread low-dose computed tomography (CT) screening should be considered. This review article is based on the health education guidance manual provided by the National Health Administration of the Ministry of Health and Welfare and jointly developed by Taiwan Lung Cancer Institute, Association of Thoracic and Intensive Care Medicine, Taiwan Association of Pulmonary and Critical Care Medicine, Taiwan Radiological Society, Taiwan Society of Thoracic Surgeons, and Formosa Cancer Foundation. It also describes who, when, and how often individuals should undergo CT-based lung cancer screening. Furthermore, follow-up and treatment recommendations for patients with positive screening results are included in this review.