A backlight module comprising a light source and a light guide plate. The light guide plate comprises a transparent substrate and a plurality of dimming units having a reflecting function. The light source is disposed on at least one side of said transparent substrate, and the plurality of dimming units is disposed on a lower surface of the transparent substrate for adjusting an emergent intensity of light, which is incident from the light source into the light guide plate, on an upper surface of said transparent substrate facing away from said dimming units. A method for controlling a backlight module and a display screen and wear device including the backlight module are also disclosed.