The process of cortical expansion in the central nervous system is a key step of mammalian brain development to ensure its physiological function.Radial glial (RG) cells are a glial cell type contributing to this progress as intermediate neural progenitor cells responsible for an increase in the number of cortical neurons.In this review,we discuss the current understanding of RG cells during neurogenesis and provide further information on the mechanisms of neurodevelopmental diseases and stem cell-related brain tumorigenesis,Knowledge of neuronal stem cell and relative diseases will bridge benchmark research through translational studies to clinical therapeutic treatments of these diseases.