Embodiments of the present disclosure provide a light guide plate, a light guide plate module, a backlight module and a display device. The light guide plate includes a light-exiting surface and a bottom surface disposed opposite to each other; and a light-entering side and a plurality of side surfaces arranged between the light-exiting surface and the bottom surface. At least one of the plurality of side surfaces is provided thereon with at least one light-deflecting structure that is configured to reflect part of light emitted from the at least one side surface to at least one selected area inside the light guide plate.