A backlight module is disclosed in the present disclosure. The backlight module comprises a reflective sheet, a printed circuit board (PCB), a diffuser plate and a supporting structure. The reflective sheet is attached onto the PCB, and the supporting structure is located between the diffuser plate and the reflective sheet. The supporting structure comprises a body portion and a supporting portion, and the PCB comprises an adapter member. By using the adapter member and the supporting structure in the backlight module of the present disclosure, the supporting structure can make contact with the PCB in a large area and support the diffuser plate stably. Further, a liquid crystal display (LCD) device using the backlight module described above is also disclosed in the present disclosure.