Free crystalline silica is very inert and widely used in industries. While entering human body, free crystalline silica will stay in lung for a long time, and cause healthy effects such as silicosis and lung cancer. The International Agency for Research on Cancer had grouped free crystalline silica as Group I, Carcinogen to humans, since 1997. In this article, we will discuss a sandblasting worker who was diagnosed lung squamous cell carcinoma after working over 30 years. Then we reviewed studies to explore association between his workplace exposure and disease.