Abstract: Oligodendrocytes are a group of highly specialized glial cells in the central nervous system. They are differentiated from oligodendrocyte precursor cells. Their main functions are to provide myelin and maintain the integrity of the axons. Early studies of oligodendrocyte cells mainly focused on the origin of oligodendrocyte precursor cells and the mechanism of their differentiation into oligodendrocyte. Currently, more attention about the oligodendrocyte cells are paid on the roles of oligodendrocyte precursor cells/ oligodendrocyte in the pathogenesis of neurodegenerative diseases and the repair of neurological damage. This article discussed the function and differentiation of oligodendrocytes, as well as their role in amyotrophic lateral sclerosis, Alzheimer's disease, Huntington's disease and multiple sclerosis.