Abstract: Analyzed quantificationally effects on water conservation of conjunctive use of surface and ground water in the Yellow River irrigation area of Ningxia. Due to large quantity of water withdrawn and discharged in the Yellow River irrigation area of Ningxia, water loss from canal systems, phreatic water evaporation are very severe, and ground water level of farmland is high. At present, water shortage is still severe in the whole Yellow River basin. Based on available ground water and existing wells in the Yellow River irrigation area, a set of wells are planed and built. It is of great significance to exploit a certain quantity of ground water and well-canal irrigation model to realize conjunctive use of surface and ground water. The results show that: with the increase of groundwater utilization, it can effectively lower ground water level (0.5～1.0 m), reduce the total water consumption from 39.64×10⁸ m³ to 29.95×10⁸ m³ and canal intake from 81.71×10⁸ m³ to 64.79×10⁸ m³.