The present invention aims to provide a growth inhibitor for cancer stem cells resistant to existing anticancer drug therapies, which growth inhibitor acts on the cells through growth inhibition and apoptosis. The growth inhibitor for cancer stem cells contains a retinoid agonist, preferably tamibarotene, alone or in combination with a rexinoid agonist, preferably bexarotene, as an effective component(s). The growth inhibitor for cancer stem cells enhances the effects of various anticancer drugs when the growth inhibitor is used in combination with the anticancer drugs.