A combined housing and air pump has a barrel type outside vessel one end of which is closed and the other end of which is open, a barrel type inside vessel one end of which is closed and the other end of which is open, and an air suction opening and an air discharge opening formed on the closed end of one of the outside vessel and the inside vessel, the inside vessel can be inserted from the opening of the outside vessel, and inside the outside vessel the outer periphery of the inside vessel is substantially very close to the inner periphery of the outside vessel and the inside vessel can rub in the axial direction of these vessels. The air suction opening has a check valve through which an air is allowed to pass only in the air suction direction, and the air discharge opening has a removable nozzle separately formed. The container can be carried with things contained in the inside space sectioned by the two vessels. And the container can be used as an air pump to inflate a balloon and so on by taking the inside vessel in and out of the outside vessel in the axial direction. It is convenient not to have to carry an air pump separately.