Excessive fertilization and frequent irrigation are common problems in facilities vegetable production of Mollisols.The effects of water and fertilization reduction on facilities greenhouse vegetables yield，soil NO 3 --N accumulation amount and soil nitrogen surplus in the soil-vegetable system in Mollisols were studied，which could provide a scientific basis foroptimizing nitrogen nutrient management technology，and reducing nitrogen loss and environmental pollution. This studytook typical Mollisols vegetable field as the research object. Four treatments were setup，including no nitrogen fertilizationtreatment(CK)，conventional water and fertilizertreatment(WF)，80% conventional watertreatment(80%WF)，and80% conventional fertilizer treatment(W80%F). This research aimed to study the effects of water and fertilization reductionon the eggplantyield，nitrogen utilizationrate，soil inorganic nitrogen accumulation and nitrogen surplus in the soil -vegetable system. Yield was significantly higher inWF，80%WF and W80%Ftreatments，compared to CK treatment. Yieldin W80%F treatment was no significant change compared with WF treatment，but yield in 80%WF treatment was significantly reduced by 6.44% to 8.40%. Nitrogen uptake did not change significantly in the water reduction and nitrogen reductiontreatments compared to the WF treatment. Nitrogen fertilizerutilization，nitrogen fertilizer agronomicefficiency，and nitrogenfertilizer bioproductivity were significantly reduced by11.00%，56.66% and 6.21% in the 80%WFtreatment，respectively，compared to the WF treatment，while nitrogen fertilizer agronomicefficiency，and nitrogen fertilizer bioproductivity weresignificantly increased by 11.22% and 24.69% in the W80%F treatment，respectively. At the same time，the accumulation of nitrate nitrogen in the 0-100 cm soil layer was significantly increased by 3.90%-7.73% in the WF treatment and significantlydecreased by 3.60%-6.07% in the W80%F treatment，compared to the WF treatment，and the soil nitrogen surplus was maintained at 195.24-234.69 kg/hm². Inaddition，soil nitrogen surplus was significantly correlated withirrigation，nitrogen application and nitrate nitrogen accumulation. The water reduction and nitrogen reduction treatments markedly increased thenitrogen surplus in the 0-60 cm soil and effectively preserved nitrate nitrogen in the 100 cm soillayer，reduced the risk of leaching and achieved the dual purpose of efficient production and reducing environmental pollution.