Immune checkpoint inhibitors(ICIs)have provided great success in cancer treatment field, and immunotherapies using ICIs have become standard therapy for several cancers. Cancer stem-like cells(CSCs)are defined by their higher tumorigenicity and resistance to chemotherapy and radiotherapy, thus they are supposed to be responsible for recurrence and distant metastasis. Therefore, control of CSCs is a key factor to improve patients' prognosis. In this review article, we summarize the expression of PD-L1, a molecular target of ICIs, in CSCs, and discuss the possibility of CSC-targeting immunotherapy using ICIs.