Abstract: The present invention provides a method for manufacturing a composite carbonate in a semi-dry manner by using combustion ash and, more specifically, provides a method for manufacturing a composite carbonate in a semi-dry manner by using combustion ash, the method comprising a step of adding a small amount of water to combustion ash containing calcium ions in an atmosphere of carbon dioxide. According to the present invention, carbon mineralization is carried out in a semi-dry manner by the manufacturing method, so that the composite carbonate can be efficiently produced. In addition, the composite carbonate can be utilized as a component for a concrete composition.