The present article deals with the patterns of soil N the uptake of soil and fertilizer N by rice plant and the fate of fertilizer N in relation to the forms and methods of placement of N fertilizer in the paddy soils of Suchow District, Jiangsu Province. Field experiment was carried out with ¹⁵N-tracer technique. The soils used for the experiment are developed from the alluvial-lacustrine deposits with a feature of clay loam.