Provided are a new method of producing cells having characteristics of hematopoietic stem/progenitor cells, for use in hematopoietic stem cell transplantation, and hematopoietic stem/progenitor cell-like cells produced by the method. Provided in particular are a method of producing hematopoietic stem/progenitor cell-like cells retaining differentiation pluripotency and self-replication potential, comprising (1) a step for providing a mammalian pro-B cell or progenitor cell thereof, and (2) a step for culturing the cell (1) above under conditions for induction of differentiation into B cells, wherein the function and/or expression of the transcription factor E2A is suppressed at least at the stage of pre-pro-B cells or pro-B cells in the process (2) above a hematopoietic stem/progenitor cell-like cell produced by the method and an immunotherapeutic agent comprising the hematopoietic stem/progenitor cell-like cell, and the like.
