An optical touch module disposed on a reference plane and having a sensing area is provided. The optical touch module includes a first light sensing device and a light source module. The first light sensing device is disposed on a first side of the sensing area. The light source module includes a linear light source, a transparent plate and a reflecting device. The linear light source is disposed beside a second side of the sensing area to emit light to the sensing area. The transparent plate is disposed between the linear light source and the second side opposite to the first side. A part of the light is reflected by the transparent plate. Another part of the light passes through the transparent plate. The reflecting device is disposed beside a second surface of the transparent plate to reflect the light reflected from the transparent plate back to the transparent plate.