The invention discloses a preparation device of an antibacterial coating of an implantable medical instrument. The instrument comprises anti-skid supporting legs, a ball mill, a mounting plate, a movable rotating rod, a temporary storage box and a fixed rotating rod, anti-skid supporting legs are welded on the lower surface of the mounting plate, a slide way is formed in one side of the inner partof the mounting plate, and a slide block is arranged in the slide way in a sliding mode; a movable rotating rod is arranged at the upper end of the sliding block, and a fixed rotating rod is arrangedon one side, deviating from the slide way, of the upper end of the mounting plate; the top of the fixed rotating rod is provided with a supporting plate, spherical bearings are installed at the top ends of the movable rotating rod and the fixed rotating rod, the ball mill is inserted into the spherical bearings, and a feeding device is arranged at the upper end of one side, close to the fixed rotating rod, of the ball mill; and a feeding hole is formed in the middle position of the feeding device, and a sealing plate is arranged at the upper end of the feeding opening in a sliding mode. According to the preparation device, the feeding can be conveniently carried out, and the surface of the raw material can be polished to be smooth through the ball mill, so that the coating effect is better.