The present disclosure relates to a backlight module for a display screen, the backlight module comprising first light-emitting units located on two sides of the backlight module and a second light-emitting unit located between the first light-emitting units on both sides, each of the first light-emitting unit and the second light-emitting unit comprising a plurality of light-emitting elements, the distance between the light-emitting elements of the first light-emitting unit and a display module of a display screen being smaller than the distance between the light-emitting elements of the second light-emitting unit and the display module of the display screen. The present disclosure also relates to a display screen comprising the backlight module, and relates to a display device comprising the display screen.