To provide an RGB backlight display device and method for a portable telephone realizing favorable image quality by controlling an electric current flowing in each LED constituting the three primary colors for maintaining constant a luminous intensity irrespective of a desired display color.

A control part 14 individually controls the timing of an output signal and 'Duty' of a rectangular wave generated at PWM part (R) 7, PWM part (G) 8, and PWM part (B) 9, causes each LED to emit light, and performs coloring of a desired display color. However, the total average electrical current flowing in an LED (RED) 1, an LED (GREEN) 2, and an LED (BLUE) 3 is maintained constant irrespective of the desired display color, and the intensity of each display color is maintained constant.