An LED module includes an LED having a central axis I, and a lens. The lens has an incident face for incidence of the light of the LED and an opposite emitting face for refracting the light of the LED out of the lens. The emitting face of the lens has a central axis II. The central axis II is offset from the central axis I and located at one side of a plane ZOX of an XYZ coordinate with an original O which is located at a center of the LED, in which the central axis I is coincident with the Z axis. The light beams emitted from the one side of the plane ZOX are stronger than the light beams emitted from the another side of the plane ZOX after the light beams emitted from the LED pass through the lens.
