Abstract: A differential gear device for a vehicle including a housing, a pinion shaft provided inside the housing, a pinion gear respectively mounted on both ends of the pinion shaft, and a pair of side gears respectively disposed on both sides of a width direction of a vehicle and engaged to the pinion gear. A disconnector actuator system is coupled to one side gear and a drive shaft is coupled to the other side gear among the pair of the side gears. The differential gear device for the vehicle includes a noise reduction unit provided between the cover to which the drive shaft is coupled and the other side gear to prevent a whine noise from being generated between the pinion gear and the other side gear during the operation of the disconnector actuator system.