A two-year field experiment was conducted to study the effects of two types of nitrogen fertilizers (urea; coated urea, CU) on maize yield, water use efficiency (WUE), nitrogen use efficiency (NUE) and dynamics of soil Nmin content (DSNC) in 2004 and 2005. Two summer maize cultivars, Zhengdan958 and ND108, were applied. The results showed that yield and WUE were increased by the increase of N input, but no significant difference was observed between urea and CU treatments. NUE of maize under CU treatment was higher than that under urea treatment, especially the diffefrence was significant under treatments of 90 kg N/hm2 (Zhengdan958) and 180 kg N/hm2 (ND108) in 2004. Effects of N application on DSNC showed annual difference. In 2004, DSNC showed “V” shape under zero N application condition, whereas transformed to “N” or inverse “V” shape after N application. In 2005, DSNC showed “N” shape under both N application and zero N application conditions. Soil Nmin content was increased by N application, especially with CU application. Nmin content was the highest in top soil layer with CU application, while higher Nmin content occurred in deeper soil layer with urea application, especially when applied 180 kg N/hm2 of urea at 9-leaf to silking stage in 2004. Coated urea showed clear slow-release effect, and simultaneously controlled the downward moving of mineral N under heavy rainfall season. Therefore, it can be speculated that coated urea can be used as a substitution of urea in maize production system in North China Plain, that help to change twice fertilization (basal and dressing) to one fertilization (basal), and thus benefit to labour-saving, profit-increasing and environment-protecting.