The invention belongs to the technical field of water transfer printing, and particularly discloses a water transfer printing device. The water transfer printing device comprises a water tank, a rackand a conveying belt parallel to the water tank; idler wheels for driving water in the water tank to flow are arranged at the bottom of the water tank; conveying chains are arranged on the two sides of the water tank correspondingly, and partition rods are clamped on the conveying chains; motors are arranged on the positions, on the two sides of the water tank, of the rack correspondingly, drivinggears are arranged on output shafts of the motors, rotating shafts are rotatably connected to the rack, and the rotating shafts are provided with driven gears engaged with the driving gears; rotatingrods are fixed to the rotating shafts, and supporting plates are hinged to the ends, away from the rotating shafts, of the rotating rods; counterweight blocks are hinged to the lower ends of the supporting plates, and concave cavities are formed in the positions, at the upper ends of the counterweight blocks, of the supporting plates; the two concave cavities corresponding to the two motors are symmetrically formed facing the water tank; and the distances between the supporting plates and the rotating shafts are not less than the distance between the two partition rods. Compared with the prior art, the water transfer printing device can automatically and continuously conduct water transfer printing machining on automobile parts, the efficiency of water transfer printing batch machining isgreatly improved, and the health of workers is also protected.