Objective: Lung cancer (LC) is one of the most common cancers in both sexes. It is also one of the deadliest forms of cancer in the world. An increase in the incidence rate of LC, coupled with the nature of its recurrence, has led to massive burden on health care system. Study findings have shown that the geographical and ethnical distribution of LC varies in different parts of the world, as in men of the Americas living in Europe, East Asia and North America it is significantly higher than sub-tropical Africa. On the other hand, most studies in this area focus mainly on LC therapies. Considering the limitations of publishing a comprehensive study with emphasis on epidemiological aspects and LC risk factors in the world, the need for studies in this field is felt. Therefore, the aim of this study is to determine the incidence and mortality rates and risk factors of LC in the world.