In this study, the Bremner method was used to measure soil organic N components and to clarify the characteristics of soil organic N components with different orchard planting ages (0, 2, 10, 20, and 30 years). The results showed that the total N contents in the orchard soils increased with the planting age. The hydrolysable unidentified N, nonacid hydrolysable N, ammonium N, amino acid N and amino sugar N accounted for about 38.9%, 25.7%, 20.5%, 9.9% and 4.9% of the increased total N in soil, respectively. The percentage of non-acid hydrolysable N increased with the planting age, while the percentage of hydrolysable unidentified N and ammonium N decreased with the planting age. Thus, the sequence of organic N components in soil changed with the planting age. The organic N mineralization rate decreased with the increased percentage of nonacid hydrolysable N, affecting inorganic N supply rate in soil.