Disclosed is a user interface apparatus for a vehicle, the apparatus including: a display unit configured to output stereoscopic content; an internal camera configured to acquire an image of the inside of the vehicle; and a processor configured to detect an image of a head of a user of the vehicle based on the image of the inside of the vehicle, generate pose information and movement information of the head based on the image of the head, and set a virtual head box based on a method for implementing the stereoscopic content, the pose information, and the movement information.