Abstract: A statistical process control guarantees the quality and reliability in modern industrial manufactures. Process capability indices can provide a general idea on the process capability of an industrial process. In this paper, we summed up the current study situation of process capability indices. A concept concerning process capability indices was introduced at first. Then, several analytical methods of process capability indices were presented in detail. Furthermore, we addressed some approaches to dealing with non-normality of the distribution. Finally, the conclusion, the future study and development on process capability indices were shown.