The application provides a backlight module, a manufacturing method thereof, and a liquid crystal display device. The backlight module includes a substrate, and a light-emitting chip and a reflective layer disposed on the substrate. Wherein, the reflective layer has a hollowed-out region, the light-emitting chip is electrically connected to the substrate in the hollowed-out region, and a projection of an edge of the hollowed-out region on the substrate is at least partially within a coverage of a projection of the light-emitting chip on the substrate to improve luminous efficiency.