A backlight module includes a case, a lamp, and a lamp clamping mechanism. The case has a bottom plate. The lamp is installed inside the case. The lamp clamping mechanism is connected to the bottom plate. The lamp clamping mechanism includes a base, a second clamping part, and a driving part. A first clamping part is disposed on the base. The second clamping part is installed on the base in a movable manner. The second clamping part is used for clamping the lamp with the first clamping part cooperatively when the second clamping part is moved to a first position so as to fix the lamp on the bottom plate. The driving part is pivotally disposed through the base. The driving part is used for rotating relative to the base so as to push the second clamping part from a second position to the first position on the base.