To provide a device for inexpensively and easily producing good-quality soda water at home.

A carbonate and an acid are put in a sealable carbon dioxide-generating vessel 1 of Fig.1, and carbon dioxide gas is generated in the sealed carbon dioxide-generating vessel by reacting the carbonate with the acid by pouring water 9 into these. The generated carbon dioxide gas is introduced to a trap 2 by using a pressure of the gas generated by the reaction in this sealed vessel, and is also introduced into a soda water production vessel 3 after removing a reaction liquid splash mixed in the gas, and the soda water is produced by promoting dissolution of the carbon dioxide into drinking water by vibration-agitating the soda water production vessel 3 while pressure-injecting the carbon dioxide gas into the inside of the drinking water.