The steam valve driving apparatus according to an embodiment is a steam valve driving apparatus regulating open and close position of a valve body. The steam valve driving apparatus includes: a plurality of hydraulic cylinders that presses the valve body in an opening direction. Each of the hydraulic cylinders includes: a piston rod extending outward from a piston in the opening direction; and an open-side cylinder chamber arranged in the opposite side of the piston with respect to the piston and to which hydraulic oil is supplied. The hydraulic cylinder is disposed on a side opposite to the valve body with respect to a closing spring pressing the valve body in a closing direction.