The invention discloses a dehydration plant for preparing coal slurry from high-sulfur coal gangue. The dehydration plant comprises a machine frame, an upper filter belt, a lower filter belt positioned below the upper filter belt, a first home roll for driving the upper filter belt, and a second home roll for driving the lower filter belt, wherein the first home roll and second home roll are matched with each other; the first home roll and second home roll are respectively connected with the machine frame and respectively positioned at a discharge port; at least two squeeze rolls for driving the upper filter belt are installed between the upper conveying surface and lower conveying surface of the upper filter belt; the squeeze rolls have the same rotation direction as the first home roll; all the squeeze rolls are parallel to the driving direction of the first home roll along the upper filter belt; each squeeze roll is a hollow roll of which the wall is hollowed out; the inner wall of each squeeze roll is covered with filter paper; and one end of each squeeze roll communicates to a vacuum pump, and the other end is sealed. The structure of the squeeze rolls is changed to combine the extrusion and vacuum filtration modes, thereby enhancing the dehydration efficiency of the coal slurry.