A material loading device includes a loading frame and at least one first locking mechanism. The loading frame defines a receiving cavity and at least one opening communicating with the receiving cavity. Opposing inner walls of the loading frame define a plurality of first slots. The at least one first locking mechanism is disposed at the at least one opening. The at least one first locking mechanism includes a first locking portion extending downwards. The first locking portion includes a plurality of second slots and a plurality of blocks adjacent to the plurality of second slots. The first locking portion can drop by gravity, driving the plurality of blocks to move to and lock the plurality of first slots. The first locking portion can also be lifted, to drive the plurality of second slots to move to and unlock the plurality of first slots.