An LED (light emitting diode) light source module includes a first optical lens, an LED light source received in a groove of the first optical lens and a second optical lens located at a light path of the LED light source and above the first optical lens. The first optical lens includes a first reflecting surface around the groove and a second reflecting surface. The second optical lens includes a reflecting surface facing the LED light source, and light which is incident to the reflecting surface of the second optical lens is reflected thereby to the first reflecting surface and the second reflecting surface of the first optical lens. A light diffusion plate is attached to the second optical lens at a position away from the reflecting surface of the second optical lens.