Foldable mounting device and method of operating the same

A foldable mounting device applicable for a photographing device, the foldable mounting device comprising:

• a base plate comprising a connecting end which comprises an accommodation slot and a connecting opening in communication with the accommodation slot, the accommodation slot comprising a slot opening which passes through a side of the base plate;
• a side plate connected to the connecting end of the base plate;
• and
• a locking member slidably received in the accommodation slot, the locking member comprising a locking part and an operation part, the operation part being received in the slot opening and exposed from the side of the base plate;
• wherein the locking member is operatable via the operation part to move from a locked state in which the locking part passes through the connecting opening to engage with the side plate such that the side plate is locked and nonrotatable relative to the base plate to an unlocked state in which the locking part is disengaged from the side plate such that the side plate is rotatable relative to the base plate.