An electromechanical actuator includes a first system and a second system. The first system includes a first motor and a first movable element capable of being moved back and forth in an axial direction of a rod. The second system includes a second motor and a second movable element capable of being moved back and forth in the axial direction of the rod. The electromechanical actuator is capable of adjusting a stroke length which is a distance between the first driving section set to or in the proximity of an end portion of the first movable element and the second driving section set to or in the proximity of an end portion of the second movable element. The first movable element and second movable element are configured for back and forth movement in the axial direction of the common rod.