Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas) protein system, as an emerging gene editing system, can be divided into class 1 and class 2 systems according to the number of Cas protein. The CRISPR/Cas9 in class 2 system can cleave target nucleic acid only with the help of Cas9 protein and single-stranded guide RNA, which is currently the most widely used CRISPR/Cas system. In addition to gene editing in the treatment of genetic diseases, a variety of CRISPR/Cas system derived technologies have vast application prospect in the fields of disease-related gene screening, gene expression regulation, and rapid detection, prevention, and control of pathogens. This article summarizes the discovery process of CRISPR/Cas system and applications of several major CRISPR/Cas derived technologies, aiming to provide a reference for researchers in the field of life science.