PROBLEM TO BE SOLVED: To provide a gas dissolver which directly and effectively dissolves a gas supplied from a gas cylinder, such as carbon dioxide, into shower water or flowing water and has a simple structure.SOLUTION: A gas dissolver is detachably attached to a passage in which flowing water passes, allows a mixture of the flowing water and a gas to pass therein to generate and discharge a gas dissolved solution, and includes: an outer cylinder having a hollow space therein； a first adapter connecting a downstream area of the outer cylinder with the passage； an inner cylinder disposed in a part of the outer cylinder located at the upstream side of the first adapter； and a second adapter connecting an upstream area of the outer cylinder with the passage. The first adapter and the second adapter sandwich and position the inner cylinder.SELECTED DRAWING: Figure 1
