Corynebacterium glutamicum (C. glutamicum) is one of important industrial microbe and its genome codes for seven sigma (σ) factors of RNA polymerase. Except σA, six other σ are alternative σ factors. The regulation of gene expression mediated by σ factors is the important part of the regulatory network of bacteria. Therefore, the research on the function and regulatory mechanism of σ factors are helpful to improve the gene regulatory network of C. glutamicum and further perfect optimizing strategy of stains in the industrial production. This paper reviews the function and regulatory mechanism of six alternative σ factors in C. glutamicum and discusses several experimental designing problems noticed in the course of studying on the function of alternative σ factors. Moreover, we also present practical application value of alternative σ factors and its future research direction for continuation. This review will provide reference for further improvement of the gene regulatory network and standardization study of alternative σ in C. glutamicum.