Abstract: The present invention provides an exercise device having a chamber maintained in an airtight condition and a seal member that can be easily attached and detached by a user. The exercise device of the present invention includes a chamber having an opening through which a user can enter or exit the chamber, a seal member for closing the opening of the chamber in an airtight manner, a pressure control unit for pressurizing the inside of the chamber, and exercise equipment housed inside the chamber, wherein an engagement ring is provided in the opening of the chamber, the seal member includes a skirt to be worn by the user and an elastic tube, the tube being attached to the outer peripheral edge of the skirt, making the outer peripheral edge of the skirt be in contact with the engagement ring, and the skirt being in close contact with the engagement ring due to pressurization of the inside of the chamber.