PURPOSE: To provide a liquid crystal display device capable of efficiently utilizing light from a fluorescent lamp.

CONSTITUTION: When the fluorescent lamp 4 is turned on, the light is emitted from the flat surface part 5a of a glass bulb 5. Simultaneously, the light emitted in the direction of a curved part 5b is reflected on a reflector 6 and emitted from the flat surface part 5a. Then, it is guided to the light guide part 7a of an acrylic light guide body 7. The light is guided by the guide body 7 to form an apparent light emitting surface on a light diffusion plate. Then, a liquid crystal display body is irradiated with the light from the light diffusion plate from the back surface thereof. Since the surface of the lamp 4 facing the guide part 7a is the flat surface part 5a and the flat surface part 5a is set in parallel with the guide part 7a, the incident angle of the light made incident on the guide body 7 is small and acute. Besides, the quantity of the light made incident on the guide part 7a is increased and the quantity of Fresnel reflection is reduced. Moreover, the light emitted from the lamp 4 is efficiently introduced from the guide part 7a and the utilizing efficiency of the light is improved. Since the shape of the cross section of the lamp 4 is approximate to a circle, an electric discharge is also stabilized.