A torque transmission device includes an engine, a motor, an output shaft, and a planetary gear mechanism. The engine and the motor generate driving torque, and the output shaft outputs the driving torque. The planetary gear mechanism includes a first rotating element rotating together with the engine, a second rotating element connected to the motor, and a third rotating element connected to the motor. The torque transmission device further includes a primary clutch, a secondary clutch, a primary brake, and a secondary brake. The primary clutch selectively transmits rotation of the second rotating element to the output shaft, and the secondary clutch selectively transmits rotation of the third rotating element to the output shaft. The primary brake selectively stops the rotation of the third rotating element, and the secondary brake selectively stops the rotation of the second rotating element.