Although the result of low dose computed tomography (LDCT) screening for high risk smoker for lung cancer (National Lung Screening Trial, NLST) showed 20% of lower lung cancer death compare to chest X-ray screening, which published in 2011, after more than 8 years passed, no European or Asian country has implemented organized lung cancer screening with LDCT, and there are no National Lung Cancer Screening Program globally. In United States, where LDCT lung screening has become standard procedure, the screening rate is extremely low, less than 5%. That is because in spite of the considerable the benefit of the screening, the harms of screening; specifically, most notably due to the high level of false positives, and physical, psychological, and economical burdens. Recently the controversies regarding the harms of LDCT lung screening has been increasingly debated. Also, the novel strategies, such as artificial intelligence and volumetric measurement of suspicious nodules has been adopted for recently launched lung cancer screening clinical trials. However, amid of skeptical opinions increasing globally, Korean Government recently decided to include LDCT lung cancer screening as national cancer screening program, becoming Korea as the first and the only national lung cancer screening program worldwide. Without randomized trial proven to be effective for Korea population, hurried implementation of national lung cancer screening program could have more harmful effect than benefit in terms of public health perspectives.