Abstract: A sprinkler system for a vehicle running test course having an incline in the direction of the width of the vehicle running test course such that said vehicle running test course has a higher side and a lower side. The sprinkler system including a concave placement channel constructed on one or both sides of the vehicle running test course; multiple sprinklers capable of sprinkling water over the vehicle running test course being installed in the concave placement channel; a concave installation channel constructed on the higher side of the vehicle running test course; and multiple water sprinkler nozzles placed in the concave installation channel. The water sprinkler nozzles sprinkle water onto the higher side of the vehicle running test course such that the sprinkled water flows downward along the surface of the vehicle running test course toward the lower side of the vehicle running test course.