Abstract: In China, the water resource is seriously inadequate, and the ecological environment becomes worse and worse. Agricultural product export is difficult because of poor quality and agricultural chemical residue. Agriculture consumes the largest part of water resources that was about 72 percent of all over the country. In one growing period, rice needs about 7 500 m³/hm² to 9 000 m³/hm² of water more than other crops. It is one of the main factors that causes environmental pollution and ecological deterioration. So, it has the important significance for economy and society to study saving water, protecting environment and raising benefit in rice production. Through testing in the field of 20 hm² at village of Liaoyang City, the effects of the technology of laser-controlled land leveling on saving water and land in the process of paddy field irrigation were studied by using automatic control theory. The results showed that by using the technology 47.46% water and 0.92% land were saved. To test the runoff of the infall, when the field was irrigated, the stopwatch and table tennis ball were used to measure the rate of water flow. It is proved that this method has the advantage of low experimental expenses, simple operation, precision and credible results.