The present invention provides a drug capable of initiating the progression of the cell cycle of leukemia stem cells to overcome the resistance of the leukemia stem cells to cell cycle-dependent chemotherapeutic agents, and a drug for suppressing recurrence of leukemia containing the same, and the like, an agent containing G-CSF, wherein the agent is for inducing the progression of the cell cycle of leukemia stem cells, a drug for suppressing recurrence of leukemia containing a combination of G-CSF and a cell cycle-dependent antitumor agent, and the like.
