An optical touch apparatus includes a first light source, a second light source, a light guide device, a light reflecting device and an image sensing module. The first light source emits first light beam which travels within the light guide device and is reflective by an object close to or in contact with a surface of the light guide device to become a first image light beam. The first image light beam is reflected by a light reflecting device. The image sensing module receives the first image light beam. The second light source emits a second light beam, wherein when the optical touch apparatus moves on a working surface, the second light beam is reflective by the working surface to form a second image light beam which is received by the same image sensing module.