【Objective】The effect of water and nitrogen fertilizer coupling with furrow irrigation under plastic film on root distribution， root/shoot ratio and yield of winter wheat was studied to provide references for winter wheat production. 【Method】Two irrigation levels of 1500 m3/ha and 3000 m3/ha and three nitrogen fertilizer level of 75，150 and 300 kg/ha were designed in this experiment to test root trait and yield of winter wheat in different treatments. 【Result】With the increase of soil depth， the amount of roots rose but root length density decreased exponentially. Under the same level of irrigation， proper increase of nitrogen fertilizer would significantly promote the growth of roots， however excessive nitrogen fertilizer inhibited root growth. Under the same level of nitrogen fertilizer， as the level of irrigation rose， the yield of winter wheat increased and the growth of root was promoted while its root/shoot ratio declined. The yield and root-shoot ratio had significant correlation and accorded with quadratic function. 【Conclusion】 The yield and root-shoot ratio had significant correlation and accorded with quadratic function. It is concluded that the 3000 m3/ha irrigation and 150 kg/ha nitrogen was the optimal fashion.