Disclosed is a headrest device for a vehicle. The headrest device may include a stationary headrest portion coupled to a seatback of the vehicle and formed to extend upwards. The stationary headrest portion may be located at a rear of a head of an occupant. The headrest device may include a movable headrest portion coupled to the stationary headrest portion so as to be slidable in a vertical direction, the movable headrest portion may be located in front of the stationary headrest portion. The headrest device may include an actuator including a first side coupled to the fixed part, and a second side coupled to the movable headrest portion. The actuator may be configured to cause the movable headrest portion to slide in the vertical direction.