To provide an apparatus for producing carbonated water capable of solving such the problem that there is a risk of accompanying a danger and improvement has to be considered, since the conventional apparatus has such a structure that a carbon dioxide gas cylinder is housed in the apparatus, the carbon dioxide gas cylinder is connected to a pressure-resistant container via a pipe, a valve is disposed in the pipe, a first valve body for discharging excessive gas and a second valve body for pouring out carbonated water are disposed in the pressure-resistant container and an operational lever for operating the first and second valve bodies is disposed, and the opening and closing operation of the carbon dioxide gas cylinder is performed only by control by means of the valve.

In the apparatus for producing carbonated water, on one side of a case body, a housing space for the carbon dioxide gas cylinder and a rotation tool for attaching the cylinder are disposed, and a needle which holds the cylinder on the rotation tool and opens the tight closure, a gas passage and an opening and closing means for opening and closing the gas passage are disposed, and on the other side of the case body, a cup housing space for housing a cup and a pressure-resistant water tank part are disposed. In the water tank, a carbonated water passage, the opening and closing valve and a cock are disposed, the gas passage of the rotation tool and the carbonated water passage are joined together with a hose and a handle for performing the opening and closing of the opening and closing means is disposed on the lateral surface of the case body.