The invention relates to a sprayer water-distributing automatic testing device for fire-fighting system. The device comprises a frame, a loading sprayer sample, a suspended ceiling, a lifting rack, a sprayer positioning device, a suspended ceiling, a positioning device of the height of the suspended ceiling, a camera, a bracket of the water-collecting box and a positioning device of the water-collecting box. The lifting rack can lift along the frame to position the sprayer sample or the suspended ceiling in the direction of the height. The sprayer positioning device is located on the lifting rack and can position the sprayer sample in the horizontal direction. The positioning device of the height of the suspended ceiling is used for adjusting the distance between the suspended ceiling and the sprayer sample. The camera is used for recording the images of the testing process. The bracket of the water-collecting box is located at the lower part of the frame and is used for collecting the water sprayed from the sprayer. The positioning device of the water-collecting box is used for positioning the bracket of the water-collecting box. The sprayer water-distributing automatic testing device for fine-fighting system has the advantages of automatically determining the distribution of the sprayer, the distance between the sprayer deflector and the suspended ceiling, the distance of the suspended ceiling from the edge of the water box and the protective areas of the water-collecting box according to the programming; and being capable of recording the testing process through the camera. The advantage of automatically determining and finishing the judgment of the testing result improves the inspection quality and the efficiency.