This experiment was conducted under greenhouse cultivation conditions to study the effects of different amounts of water and nitrogen on tomato yield,quality,and utilization of water and fertilizer,with a view to providing scientific water and nitrogen management basis for greenhouse tomato production.The results showed that there was a certain interaction between irrigation and nitrogen application rate in organic and inorganic application mode,and had a good antagonistic effect on tomato yield,total nitrogen content,and water and nitrogen use efficiency.This experiment shows that adequate water supply and appropriate amount of nitrogen application are guaranteed for yield and improving the utilization of water and nitrogen for tomato production.Under the same amount of nitrogen applied,the content of soluble sugar,soluble acid and Vc in the quality of tomato increased firstly and then decreased with the increase of nitrogen application rate; under the same amount of nitrogen applied,the nitrogen fertilizer and water use efficiency of watersaving irrigation were significantly higher than those of traditional irrigation,which increased by 3.07% and 5.40% compared with traditional irrigation treatments The agroutilization efficiency and partial fertilizer productivity of watersaving irrigation treatment increased by 23.61%~29.58% and 3.07%~5.49% compared with traditional irrigation.Compared with traditional irrigation,the water use efficiency of watersaving irrigation increased by 54.60% and 58.64%,and the yield and water and nitrogen use efficiency were the highest with nitrogen application amount of 675 kg/hm2 under watersaving irrigation.Under the conditions of this experiment,the treatment of W2N675 with nitrogen application rate of 675 kg/hm2 under watersaving irrigation conditions was a suitable measure for the growth and development of tomato.