A carbon dioxide recovery system includes a high-pressure 11, a boiler 15, a carbon dioxide recovery unit 24 that includes a carbon dioxide absorber 21 that absorbs and reduces carbon dioxide in flue gas G emitted from the boiler 15 using a carbon dioxide absorbent and an absorbent regenerator 23 that regenerates a carbon dioxide absorbent having absorbed the carbon dioxide using a regenerating superheater 22 to obtain a regenerated carbon dioxide absorbent, a high-temperature and high-pressure steam extraction line L11 that extracts the high-temperature and high-pressure steam 14 from the boiler 15 before the steam is introduced into the high-pressure turbine 11, an auxiliary turbine 32 that recovers power with the high-temperature and high-pressure steam 14, and a steam supply line L12 that supplies emission steam 33 emitted from the auxiliary turbine 32 to the regenerating superheater 22 to be used as a heat source.