A vehicle drive system comprising: a rotating electric machine; an output member drivingly coupled to a wheel; a differential gear device provided in a power transmission path between the rotating electric machine and the output member, the differential gear device including at least a first rotating element drivingly coupled to the rotating electric machine, a second rotating element drivingly coupled to the output member, and a third rotating element that is selectively fixed by a selectable one-way clutch to a non-rotating member and that is selectively fixed by a friction brake to the non-rotating member; and a clutch that selectively couples together two of the first rotating element, the second rotating element, and the third rotating element, wherein a reaction force torque that acts on the third rotating element when the rotating electric machine outputs a positive torque in a forward powering direction is defined as a first reaction force torque, a reaction force torque that acts on the third rotating element when the rotating electric machine outputs a negative torque opposite in direction to the positive torque is defined as a second reaction force torque, the selectable one-way clutch is structured to be switchable at least between a one-way restriction state in which rotation of the third rotating element in one direction is restricted and a rotation restriction state in which rotation of the third rotating element in both directions is restricted, in the one-way restriction state, the selectable one-way clutch restricts rotation of the third rotating element in a rotation direction caused by the first reaction force torque while allowing rotation of the third rotating element in a rotation direction caused by the second reaction force torque, the vehicle drive system further comprises a control device that controls an engagement state of each of the clutch and the friction brake and that controls a switching state of the selectable one-way clutch between the one-way restriction state and the rotation restriction state, from a situation where the rotating electric machine outputs the negative torque with the clutch engaged, the control device brings the friction brake into slip engagement while disengaging the clutch so as to reduce a rotational speed of the third rotating element, and then brings the selectable one-way clutch into the rotation restriction state when the rotational speed of the third rotating element becomes zero, and after bringing the selectable one-way clutch into the rotation restriction state, the control device maintains the rotation restriction state during a time that the rotating electric machine outputs the negative torque. a rotating electric machine; an output member drivingly coupled to a wheel; a differential gear device provided in a power transmission path between the rotating electric machine and the output member, the differential gear device including at least a first rotating element drivingly coupled to the rotating electric machine, a second rotating element drivingly coupled to the output member, and a third rotating element that is selectively fixed by a selectable one-way clutch to a non-rotating member and that is selectively fixed by a friction brake to the non-rotating member; and a clutch that selectively couples together two of the first rotating element, the second rotating element, and the third rotating element, wherein a reaction force torque that acts on the third rotating element when the rotating electric machine outputs a positive torque in a forward powering direction is defined as a first reaction force torque, a reaction force torque that acts on the third rotating element when the rotating electric machine outputs a negative torque opposite in direction to the positive torque is defined as a second reaction force torque, the selectable one-way clutch is structured to be switchable at least between a one-way restriction state in which rotation of the third rotating element in one direction is restricted and a rotation restriction state in which rotation of the third rotating element in both directions is restricted, in the one-way restriction state, the selectable one-way clutch restricts rotation of the third rotating element in a rotation direction caused by the first reaction force torque while allowing rotation of the third rotating element in a rotation direction caused by the second reaction force torque, the vehicle drive system further comprises a control device that controls an engagement state of each of the clutch and the friction brake and that controls a switching state of the selectable one-way clutch between the one-way restriction state and the rotation restriction state, from a situation where the rotating electric machine outputs the negative torque with the clutch engaged, the control device brings the friction brake into slip engagement while disengaging the clutch so as to reduce a rotational speed of the third rotating element, and then brings the selectable one-way clutch into the rotation restriction state when the rotational speed of the third rotating element becomes zero, and after bringing the selectable one-way clutch into the rotation restriction state, the control device maintains the rotation restriction state during a time that the rotating electric machine outputs the negative torque.