An industrial robot, having a manipulative robot hand for mounted on a vertically movable portion thereof moved by a vertical drive, provided with a load reducing pneumatic cylinder for applying a constant upward force to the vertically movable portion during the vertical movement of the portion and an air storage tank or tanks directly connected to the pneumatic cylinder for continuously supplying air under a desired fixed pressure. The upward force contributes to reducing a load applied to the vertical drive. The air storage tank or tanks contributes to ensuring mechanical rigidity of the industrial robot.