The present disclosure provides a driving method of a display module, a driving system thereof, and a display device. The driving method of the display module includes a display panel driving process, and a backlight module driving process driven synchronously with the display panel driving process. The display panel driving process includes steps: performing a color saturation adjustment; and obtaining second color signals to drive the display panel by converting. The backlight module driving process includes steps: using the light source adjustment coefficient to adjust a first brightness value to obtain a second brightness value; determining a dominant hue light source; and driving the dominant hue light source by the second brightness value.