A cold cathode fluorescent lamp includes: a working gas, a transparent tube, a fluorescent layer, an anode, a cold cathode and a light cut filter film. The transparent tube receives a working gas, and has an inner surface and an outer surface. The fluorescent layer is formed on the inner surface of the transparent tube. The light cut filter film is formed on the outer surface of the transparent tube. The cold cathode is disposed at one end of the transparent tube and the anode is disposed at the other end of the transparent tube. The cold cathode fluorescent lamp can block most part of the ultraviolet lights and infrared lights to irradiate at the light guide plate, whereby the light guide plate has a long service life without following problems such as thermal deformation, deflection, turn color and transformation.