The utility model relates to the pharmaceutical industry transfusion checking device field, and provides a novel transfusion bag welding quality checking device comprising a water tank; one side of the water tank is provided with a pressure control device; a triangle rack is arranged in the water tank, a top of the rack is connected with an inner wall of the water tank through a rotary button, a bottom of the rack is provided with a bottom plate, and the rack is also connected with a cylinder; the checking device can directly place the transfusion bag on the bottom plate; the transfusion bag is tightly pressed by a piston connected with the cylinder, and the whole rack is rotated, the bag body and rotate to a position having 30-75 degree angle with the horizontal direction; air in the bag can gather to a bag pipe or a bag bottom; welding positions on two sides of the bag body can be checked, so leak detection can be completed through observing whether consistent bubbles can be spotted or not; compared with the prior art, the transfusion bag welding quality checking device is more direct, thus greatly improving micro-leak condition detection rate.