Modern tablet devices with high performance and mobility have been widely used in daily life. The tablet computers are used in various environments that are a crowded commuter train, a kitchen for cooking and so on. In those environments, users cannot use their hands to operate a computer. Although it is effective to operate the computer by gaze, a precise gaze tracking device is required, such as an infrared camera or multiple cameras. This paper proposes a gaze gesture classification method with HMM even in a coarse gaze device.