In this study, we investigated the function of CX3CR1 in human microglia using human iPS cell-derived microglia-like cells. We found an increased inflammatory responses and phagocytic activity in CX3CR1 KO microglia-like cells as compared to wild-type microglia-like cells, suggesting that CX3CR1 in human microglia may contribute to microglial homeostasis by regulating inflammatory response and phagocytosis.