The present invention provides a side-edge backlight module, which includes a backplane, a backlight source arranged inside the backplane, and a light guide plate arranged inside the backplane. The backplane and the backlight source receive an aluminum-extruded heat sink arranged therebetween. The aluminum-extruded heat sink includes a first mounting section and a second mounting section perpendicularly connected to the first mounting section. The backlight source is mounted on the first mounting section. The first mounting section forms a slope surface at a location close to the second mounting section. The slope surface is arranged to extend from connection of the first and second mounting sections toward the backlight source. The side-edge backlight module forms a slope surface at a lower end of the first mounting section of the aluminum-extruded heat sink to eliminate potential interference issue of assembling occurring in the known techniques.