A suction device includes an adapter having in the interior thereof a supply passage to which a negative pressure fluid is supplied, a bellows connected to a distal end of the adapter, and a pad member disposed at a distal end of the bellows and to which a workpiece is attracted under suction. In addition, the suction device attracts the workpiece under suction by a negative pressure fluid which is supplied to the pad member through the supply passage and the bellows. An attachment which is capable of being tilted with respect to the axis of the bellows is provided in the interior of the bellows. In the attachment, a main body portion thereof is disposed in facing relation to a suction surface of a skirt, and a shaft portion is inserted into the supply passage at a time that the workpiece is attracted under suction.