Abstract: 【Objectives】 Drip irrigation could effectively inhibit nutrient leakage as water and nutrients can be accurately sent to close the crop root zone. In this paper, the soil mineral N contents and environmental qualities were detected under different N rates and drip irrigation, to provide a base for efficient N management in vegetable production. 【Methods】 A three-years' feild experiment was conducted with winter-spring cucumber and autumn-winter tomato double cropping system in a greenhouse. Four N rates were applied as 0, 300, 600, 900 kg/hm2 for cucumber and 0, 225, 450, 675 kg/hm2 for tomato under drip irrigation (correspondingly recorded as N0, N1, N2, N3). The mineral nitrogen contents, salinity (EC5∶1) and acidity (pH) of 0-100 cm soil depth were investigated, and the economic and environmental efficiencies of N were calculated.【Results】 As the elongation of the cropping year, the NO3--N contents under N2 and N3 treatments in 0-100 cm soil profile were significantly increased from 14.4-31.1 and 14.9-41.0 mg/kg in cucumber season in 2008, respectively, to 76.4-119.8 and 129.0-184.5 mg/kg in tomato season in 2010, respectively, increased by 0.3-1.8 and 0.5-2.0 times respectively. The electrical conductivity (EC5∶1) of 0-100 cm soil profile under N2 and N3 was significantly increased from 379.6-514.3 and 407.0-476.7 S/cm, respectively, to 663.0-1212.4 and 710.0-1359.6 S/cm of tomato season in 2010, respectively, increased by 0.3-1.8 and 0.5-2.0 times. The N rates in N1 was 33.3%-50% of N2 and N3. Compared with N2 and N3, the NO3--N content and EC5∶1 of N1 decreased by 35.5%-67.4% and 6.0%-25.2% after three years cultivation, and the pH and NUE increased by 0.06-0.18 unit and 9.0-13.8 percentage points.【Conclusions】 Under this condition, the proper N rate for winter-spring cucumber and autumn-winter tomato was recommend as N 300 and 225 kg/hm2. In most crop seasons (5 seasons), the NO3--N contents in 0-60 cm depth were in the proper range for cucumber and tomato growth, and no significant accumulation of NO3--N was observed below 60 cm in the soil under this recommended N rate.