The present invention relates to a manufacturing method of continuously carbonate such as purified MgCO_3 and CaCO_3 to be used as resources by putting carbon dioxide in seawater, comprising the steps of (S1) adding CaO or Ca(OH)_2 to a sea water solution and accordingly manufacturing Mg(OH)_2; and (S2) removing an upper layer solution in the treated sea water solution of the (S1) and separating the lower layer solution with Mg(OH)_2.
