A smelting and stirring integrated high-temperature smelting furnace for preparing a magnesium-based composite material, said furnace comprising: a crucible (1) for accommodating a material; a main body (2) for accommodating the crucible (1); and a cover body (3) that is disposed at the top of the main body (2) and that seals the accommodating space of the main body (2); further comprising a stirring unit (4), which has a first state in which said unit stirs the material in the crucible (1), and a second state in which said unit is connected to the cover body (3) and is thus distant from the crucible (1); and a power unit (5), which drives the stirring unit (4) to perform linear motion so as to switch between the first state and the second state, and which provides rotational power for the stirring unit (4). A stirring unit (4) that is continuously located in the sealed space limited by the cover body (3) and the main body (2) is provided. By means of switching between the two states, the execution of stirring action and the accommodating state can be achieved separately. Through the improvement of the stirring unit (4), the probability of introducing air can be effectively reduced, thereby preventing air and magnesium from reacting to form inclusions and entering the inside of a melt along with a stirring paddle (41).