A gas-containing unit and a water vehicle including the same are disclosed. The gas-containing unit includes a pair of reinforcement boards that are positioned in line with each other, a tube member that is positioned between the reinforcement boards and is capable of gas injection, and a support frame that is furnished along the outer circumference of the pair of reinforcement boards to connect the pair of reinforcement boards to each other. It is possible to prevent damage such as scratching and tearing of a soft tube material due to external shock, and to improve overall structural strength.