This paper presents a wearable eye tracker which is able to estimate the coordinates of point-of-gaze (POG) in 3D. By using this model, constructed by the glint (corneal reflection of IR LED) and the image of pupil center, the coordinates of POG can be estimated by calculating the intersection point of gaze-line (or visual axis) and screen. Aside from using in computer monitor, this eye tracker can apply in real 3D scene environment because it is wearable. An eye tracker is a device that analyzes eye movements, commonly applied to experiment of market research and psychology. Recently, it also has gained applications in military devices and consumer electronics.