For the purpose of fixing CO2 to concrete, a method for manufacturing concrete using carbonated cement slurry was examined. In the process of injecting CO2 into the cement slurry, more than 90% of the injected CO2 is fixed as fine calcium carbonate particles. Concrete using carbonated cement slurry did not cause a decrease in fluidity due to two-stage mixing method and showed the same level of strength development and durability as blanks. The amount of CO2 in concrete exceeded 20 kg per ton of cement. In addition, it was possible to manufacture concrete with CO2 fixed in the actual plant.