An LED driving circuit, an LED driving method, and a liquid crystal display device, which prevent deterioration of display quality by effectively shortening the time required for starting the LED backlight and stabilizing the driving operations are provided. The LED driving circuit for controlling an LED circuit constituted with one LED or two or more LEDs includes: a duty ratio adjusting circuit unit which generates/outputs adjusting signals for adjusting drive of the LED based on a PWM dimming signal inputted from outside; and a booster circuit unit which applies driving voltages to the LED circuit according to the adjusting signal outputted from the duty ratio adjusting circuit unit. The duty ratio adjusting circuit unit sets the adjusting signal to have a larger duty ratio than that of the PWM dimming signal within an adjusting period set after the power is supplied until the LED circuit starts to connect electrically.