The invention provides a position-limiting structure for a backlight module, a backlight module and a display device, belongs to the field of display technology, and can solve the problem in the prior art that an alignment error occurs in the light-guiding plate due to the fact that the double-sided adhesive tape is adhered to fix the backplane and the light-guiding plate. The position-limiting structure for a backlight module of the invention is made of an elastic material, and is configured to be connected to the backplane; the position-limiting structure includes the position-limiting part, which is arranged outside an edge at least one non light-incoming side of the light-guiding plate and is configured to fix the light-guiding plate to the backplane.