To provide a pressurized container which can dissolve a proper amount of air into the water pressurized and introduced in a tank.

A water inlet 32 is formed at the upper edge of a tank 31 in which an air-containing water is pressurized and introduced, and a lead-out port of water is formed at the lower edge of the tank 31. A partition plate 34 for partitioning the inside of the tank 31 up and down is provided below the water inlet 32 while having an interval between the water inlet and the partition plate, and a predetermined setting space S is formed between the outer peripheral edge of the partition plate 34 and the inner peripheral wall of the tank 31. The water poured from the inlet 32 falls on the partition plate 34, passes through the space S and falls on the lower side of the tank 31 along the surface of the inner peripheral wall of the tank 31 to be stored while agitating. Thereby, the undissolved air in the tank 31 is dissolved into water, and the layer of the undissolved air in the tank 31 is formed between the level of water stored at the lower side of the partition plate 34 and the lower face of the partition plate 34. The electrodes 35 and 36 for water level detection are provided in the tank.