A control method of a head mounted display (HMD) is disclosed. The control method of the HMD includes detecting a first route of a first moving object and a second route of a second moving object in front of the HMD, detecting a third route along which user's eye gaze moves, setting the first moving object as a reference object if the detected first route is substantially identical with the detected third route, setting the second moving object as the reference object if the detected second route is substantially identical with the detected third route, and performing an eye gaze calibration based on a route of the set reference object and the detected third route.