Oligodendroglial lineage cells (OLGs) are important cell reserves for myelination and remyelination. Recent studies of central nervous system (CNS) indicated that besides traditional CNS immune cells like microglia, primitive cells of oligodendroglial lineage, oligodendrocyte progenitor cells (OPCs) can also actively participate immune responses. Simulated by physiological or pathological factors, OPCs can express a series of receptors，signaling and/or regulatory molecules et al, in this way，OPCs can play a critical role in both development and maintenance of the blood-cerebrospinal fluid barrier (BCB), and most essentially, in initial stage for recruitment of peripheral immune cells and initial immune activation. Besides, in neurological disorders, recent research has revealed that OPCs can transform to disease-specific cell states, characterized by activation of immune cell exclusive genes. These findings may provide the basis for a new insight into the therapeutic strategy of neuron disorders and neurovascular diseases by effectively regulating OPCs.