Root function in uptake of nutrients and the effect of soil water on the transfer and distribution of NO3--N in arable soilwere studied using summer maize (Zea mays L. var. Shandan 9) as a testing crop. Results showed that root growth andwater supply had a significant effect on NO3--N transfer and made NO3--N distributed evenly from bulk soil to rhizospheresoil. Under a natural condition with irrigation, the difference of NO3--N concentration at different distance points from amaize plant was smaller, while obvious difference of NO3--N concentration was observed under conditions of limited rootgrowth space without irrigation. Whether root growth space was restricted or not, the content of soil NO3--N decreasedgradually from 10 to 0 cm from the plant, being opposite to the root absorbing area in soils. When root-grown space waslimited, changes of NO3--N concentration at different distances from a plant were similar to that of water content intendency. Results showed that NO3--N could be transferred as solute to plant root systems with water uptake by plants.However, the transfer and distribution of NH4+-N were not influenced by root growth and soil water supply, being differentto NO3--N. Root function in uptake of nutrients and the effect of soil water on the transfer and distribution of NO3-N in arable soil we studied using summer maize (Zea mays L. var. Shandan 9) as a testing crop. Results showed that root growth and water supply had a significant effect on NO3 - N transfer and made NO3 - N distributed evenly from bulk soil to rhizospheresoil. The difference of NO3 - N concentration at different distance points from amaize plant was smaller, while the obvious difference of NO3 - N concentration was observed under conditions of limited rootgrowth space without irrigation. whether root of space was restricted or not, the content of soil NO3 - N decreasedgradually from 10 to 0 cm from the plant, being opposite to the root absorbing area was soils. When root-grown space waslimited, changes of NO3- N concentration at different distances from a plant were similar to that of water content intendency. Results showed that NO3 - N could be transferred as solute to plant root systems with water uptake by plants. However, the transfer and distribution of NH4 + -N were not influenced by root growth and soil water supply, being different to NO3-N.