A kind of eye-gaze input sensing model based on the pupil’s relative offset to the reflection point on the cornea (Purkinje spot) from an assistant infrared light source in front of the user’s head, has been completely set up. A set of control strategy that can adapt to the user’s head movement, has also been put forwards. It can effectively overcome the difficulties existing in the similar systems that the user’s head should be stationary or just allowed a little movement while the system works. Therefore it is a spontaneous and harmonious human-computer interaction system. Moreover, this system has the obvious merits such as convenient to use, non-contact, non-wear, non-interference, non-restraint, and so on. An experiment eye-gaze input platform for human-computer interaction has been built, and the sensing and controlling model have been verified.