A greenhouse experiment for double-cropping tomato was carried out with drip irrigation in the Yellow River irrigation area of Ningxia to determine the effects of N fertilizer rate on tomato yield, apparent N recovery and soil NO₃^--N accumulation, and to analyze N balance in the tomato crop-soil system. Both yields (fruits+stems) and the aboveground N uptake increased significantly （204-232.6 kg/hm²）with N application for autumn-winter tomato in 2004, but only the treatment at N200 showed higher fruit yields （120 kg/hm² ）for winter-spring tomato in 2005, as compared with the control treatment （106 kg/hm² ）. The apparent N recovery by tomato plants decreased （3.3%-10.9% ）with increasing N rate for both seasons. The residual NO₃^--N in the topsoil (0-30 cm) was high （200-650 kg/hm² ）after autumn-winter tomato harvest in 2004, especially increased with increasing N rate. The NO₃^--N in the top 30 cm layer tended to move downward to the above 90 cm layer （250-380 kg/hm² ）after winter-spring tomato harvest in 2005. The fertilizer N rates for getting high tomato fruit yield and N recovery, but low residual soil NO₃^--N should be optimized at a range of 100-200 kg N/hm² for the autumn-winter tomato and 200-400 kg N/hm² for the winter-spring tomato, respectively.