Disclosed are liquid crystal display control method and system, and a display device. The liquid crystal display control method comprises: performing a decoding operation on input video signals to obtain data corresponding to respective pixels of a display panel; dividing the display panel into a plurality of display regions so that each display region corresponds to one or more light sources of a backlight source and a symmetric center of the one or more light sources is positioned such that an orthographic projection thereof on the display panel is coincided with a center of the corresponding display region; calculating a control signal for controlling display of each display region based on the data corresponding to pixels in the display region; redividing each display region into a plurality of subregions based on a light distribution in the display region and regulating the control signal for controlling the display of each subregion based on data corresponding to pixels in the subregion; and controlling the display panel and the backlight source based on the regulated control signals.