An optical touch module includes a transparent substrate and two light processing units. The transparent substrate includes a touch surface, a sub-surface parallel to the touch surface, and a surrounding side surface connected to the touch surface and the sub-surface. The two light processing units are positioned on two neighboring corners of the transparent substrate, and each of the two light processing units includes a light source and a detector. The light source and the detector respectively have a light emitting surface and a light entry surface, the light emitting surface of the light source and the light entry surface of the detector both face the surrounding side surface, and the two light processing units are positioned beneath the touch surface.