A hydraulically controlled gripper tool for positioning, mounting and retrieving parts in poorly accessible locations and areas, such as in nuclear power plants, includes a support body. A pivot shaft is supported on the support body in a given plane. A bracket is supported on the pivot shaft and a tilting shaft is supported on the bracket in the given plane. A basic tool body is supported on the tilting shaft. An actuation cylinder is disposed on the basic tool body and gripper jaws are connected to the actuation cylinder for closing and opening the gripper jaws. Another cylinder is rotatably disposed on the support body with a piston guided in the other cylinder and a universal joint connected to the piston. A tilting lever has one end rotatably connected to the universal joint and another end locked on the basic tool body for tilting the gripper jaws. A further cylinder is rotatably disposed on the support body and another piston is guided in the further cylinder. A joint eccentrically disposed on the bracket is connected to the other piston for pivoting the gripper jaws.