Abstract: Mature trees of Prunus mume trees/wild peach were fertilized with 15N-labelled ammonium sulphate via leaf in summer. The 15N absorbed concentrated greatly in leaves and 1-year branch on 93th days after treatment. During dormancy, the NDFF of flower bud was the highest. In the next season, the NDFF of spring shoot and young fruit was higher than other organs, and the NDFF of the former was 2.26 times higher than that of the later. The nitrogen concentration of spring shoots developing on 15N –applied 2-year branches was 14.3% higher than on water-applied branches. At the same time，a little 15N transported in the new organs near treated branches. Following summer leaf-application 15N, the withdrawn 15N from fallen leaves shifted in trees in winter, and local withdrawn 15N remobilized in original organs during spring. Summer leaf-application nitrogen was advantage to spring shoot, flower-bud differentiation and fruit-setting, and little effect to perennial organ-developing and root-expanding.