The present disclosure discloses a backlight self-adaptive adjustment method, including: acquiring a frame of picture every preset time interval when in video mode; judging whether the first picture satisfies a preset backlight self-adaptive adjustment condition, according to the brightness difference value between a first picture currently acquired and a second picture acquired within the current preset time period, and the amount of white pixels of the first picture; acquiring the brightness value of a pixel in a third picture captured from current ambient by a camera, when the first picture satisfies the preset backlight self-adaptive adjustment condition; setting the backlight value of the display video window area of the display screen based on the brightness value of the pixel in the third picture. The disclosure also discloses a backlight self-adaptive adjustment device.