Nitrogen fertilizer is a potential contaminant of ground water. The purpose of this study was to determine influ ence of rate and timing of N fertilizer application on N movement in the soil during the crop growing season. Wheat and maize were grown alternately at Yangling, Shaanxi Province from Oct., 1994 to Oct., 1996. An experiment was conducted on effect of N application rate on N movement in cumulic cinnamon soil using urea with four rates that ranged from N 130~520 kg hm^-2 a^-1 and an experiment on effect of timing of N application on the same soil with three rates and four timings from Oct., 1994 to Oct., 1995. The two experiments were laid out in a randomized complete block with three replications. After each crop harvest, the soil was sampled to a depth of 400 cm and analyzed for nitrate nitrogen. Nitrogen rate had no influence on nitrate N movement in the soil after two years, but NO₃^--N had moved down beyond 200 cm in treatments with N rate higher than 130 kg hm^-2 a^-1. N rate increased NO₃^--N accumulation in the soil. The total recovery of N ranged from 62% to 82.7%, higher with wheat than with maize. Timing of application did not influence N fertilizer movement and N recovery, either. It was found that for irrigated wheat-maize rotation system in the region, most of the N recovered came from the top 200 cm of soil, regardless of N fertilizer practices.