Abstract: A two-year (2011-2012 and 2012-2013) field experiment was conducted on one winter wheat cultivar supplied with two levels of nitrogen (180 and 240 kg N·hm^-2) under three plant densities (135×10⁴, 270×10⁴, and 405×10⁴ plants·hm^-2) . The ¹⁵Nlabeled urea was injected into 20, 60 and 100 cm soil depths, respectively, aiming to investigate the effect of nitrogen and plant density and their interaction on the N uptake, utilization and nitrate nitrogen contents at different soil depths. The results showed that increasing the plant density from 135×10⁴ to 405×10⁴ plants·hm^-2 significantly increased the ¹⁵N uptake at depths of 20, 60 and 100 cm averagely by 1.86, 2.28 and 2.51 kg·hm^-2, respectively, and increased the above ground N uptake (AGN), N uptake efficiency (UPE) averagely by 12.6% and 12.6%, respectively, but decreased the N utilization efficiency (UTE) by 5.4%. Compared to the N input of 240 kg N·hm^-2, the 180 kg N·hm^-2 significantly reduced the ¹⁵N uptake at depths of 20 and 60 cm averagely by 4.11 and 1.21 kg·hm^-2, respectively, and significantly increased the ^15N uptake at depths of 100 cm averagely by 1.02 kg·hm^-2. Reducing the N input decreased the AGN averagely by 13.5%, but significantly increased the UPE and UTE by 9.4% and 12.2%, respectively. Equivalent grain yield was observed among N input of 180 kg N·hm^-2 with plant density of 405×10⁴ plants·hm^-2 and N input of 240 kg N·hm^-2 with plant densities of 270×10⁴ and 405×10⁴ plants·hm^-2. Increasing the plant density or reducing the N input could encourage the N uptake at deep soil profile and increased UPE and UTE by 13.4% and 11.9%, respectively. Meanwhile, both the nitrate nitrogen contents in 0-200 cm soil layers at maturity and the ratio of the nitrate nitrogen in 100-200 cm soil layers to that in 0-200 cm were significantly decreased. Therefore, properly decreasing the N input with increasing the plant density of winter wheat was efficient in absorbing N at deep soil, synergistically obtaining high grain yield, UPE and UTE, and reducing the pollution of residual soil nitrate.