The invention belongs to a method and system for self-cleaning water-saving type comprehensive vehicle washing for a civil construction site. The method comprises the steps of foundation ditch precipitation well and drainage ditch system construction, cofferdam pool construction, construction of a wheel washing machine base, a water storage pool, a wheel washing pool, a filtering pool and a settling pool and the like. The system comprises the wheel washing pool used for conducting primary cleaning on tires of a muck vehicle and sludge on a vehicle body, the wheel washing machine base, a wheel washing machine, a foundation ditch precipitation well, a foundation ditch drainage ditch, a cofferdam pool, the water storage pool, the filtering pool and the settling pool. The method and system for self-cleaning water-saving type comprehensive vehicle washing for the civil construction site have the advantages that the method and structure are novel and simple, the vehicle washing efficiency is high, the vehicle washing effect is good, and environment beautifying, energy conservation, environment protection and water recovery circulation utilization are good.