A backlight module includes at least one light source and a light guide plate. The light guide plate includes at least one light incident surface, a light-emitting surface, a bottom surface, a plurality of lenticular lenses and a plurality of micro dots. The light incident surface is disposed adjacent to the light source, and the light-emitting surface is connected with the light incident surface and forms an angle with the light incident surface. The bottom surface is connected with the light incident surface and disposed opposite the light-emitting surface. The lenticular lenses are arranged on the light-emitting surface in a direction substantially parallel to the light incident surface, and the micro dots are formed on at least the bottom surface. The invention provides a backlight module having high directionality of light propagation and high light-utilization efficiency.