The invention discloses a mounting frame, a backlight module set, a display module set and a display device and belongs to the technical field of backlight module set structures. The invention aims tosolve the problem that the working reliability of a backlight module set in the prior art is low. The mounting frame comprises a bottom plate and side plates arranged at the periphery of the bottom plate; openings are formed in positions of the bottom plate which are close to the side plates; and the openings are used for enabling light sources to extend out of the mounting frame. The mounting frame of the invention can be used in a display device.